Merge pull request #1 from prashantsinalkar/masterHEADmaster

Initial commit

15 files changed, 5413 insertions, 0 deletions

diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/1-Heat_And_Temperature_Thermometry.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/1-Heat_And_Temperature_Thermometry.ipynb
new file mode 100644
index 0000000..4a4293f
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/1-Heat_And_Temperature_Thermometry.ipynb
@@ -0,0 +1,328 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 1: Heat And Temperature Thermometry"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.10: chapter_1_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"T1=25//c\n",
+"T2=15//c\n",
+"r=1.035\n",
+"//CALCULATIONS\n",
+"s=(r-1)/(T1-(T2*r))\n",
+"t=-1/s\n",
+"//reults\n",
+"printf(' absolute zero= % 1f C',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.1: chapter_1_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"n=2\n",
+"//CALCULATIONS\n",
+"t= 160/(5*n-9)\n",
+"//RESULTS\n",
+"printf (' Temperature of the fahrenheit scale= % f C',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.2: chapter_1_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"n= 1/1000\n",
+"T= 60 //degrees\n",
+"T1= 100 //degrees\n",
+"//CALCULATIONS\n",
+"r= T-n*T^2\n",
+"r1= T1-n*T1^2\n",
+"tl= r*100/r1\n",
+"//RESULTS\n",
+"printf (' liquid temperature= % 1f C',tl)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.3: chapter_1_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"p=1.0//metres\n",
+"p0=0.8//metres\n",
+"p100=1.093//metres\n",
+"//CALCULATIONS\n",
+"t=((p-p0)*100/(p100-p0))\n",
+"//RESULTS\n",
+"printf(' temperature of hot water= % 1f C',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.4: chapter_1_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"p0=0.70//metres\n",
+"LC=0.1//millimetres\n",
+"t= 100 //degrees\n",
+"//CALCULATIONS\n",
+"p100=p0*(1+(t/273))\n",
+"T=(LC/(p100-p0))\n",
+"//results\n",
+"printf(' accuracy we can expect= % 1f C',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.5: chapter_1_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"t=80//celsius\n",
+"tp=80.2//celsius\n",
+"T=120\n",
+"//CALCULATIONS\n",
+"s=(10000)*((t-tp)/(t*(t-100)))\n",
+"Tp=T-((s*t*(T-100))/10000)\n",
+"//results\n",
+"printf(' temperature= % 1f C',Tp)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.6: chapter_1_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"R100=5.93//ohms\n",
+"Ro=5.0//ohms\n",
+"P100=1.366//metres\n",
+"Po=1//metres\n",
+"Pt=1.3111//metres\n",
+"Rt=5.795//ohms\n",
+"//calculations\n",
+"tp=(Rt-Ro)*100/(R100-Ro)\n",
+"t=(Pt-Po)*100/(P100-Po)\n",
+"//results\n",
+"printf(' thermal on platinum scale= % 2f C',tp)\n",
+"printf(' thermal on gas scale= % 1f C',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.7: chapter_1_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"Rt=13.3//ohms\n",
+"R100=7.0//ohms\n",
+"R0=5.0//ohms\n",
+"t=444.6//celsius\n",
+"RT=9.1//ohms\n",
+"//CALCULATIONS\n",
+"tp=(Rt-R0)*100/(R100-R0)\n",
+"Tp=(RT-R0)*100/(R100-R0)\n",
+"s=(t-tp)*10000/(t*(t-100))\n",
+"T=Tp+((s*(Tp*(Tp-100)))/10000)\n",
+"Ts=Tp+((s*T*(T-100))/10000)\n",
+"//results\n",
+"printf(' platinum temperature of bath= % 2f C',T)\n",
+"printf(' gas temperature of bath= % 2f C',Ts)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.8: chapter_1_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"et=3.92//millivolts\n",
+"e100=0.65//millivolts\n",
+"e0=0//millivolts\n",
+"e=2//volts\n",
+"lp=1000//centimetres\n",
+"ld=50.2//centimetres\n",
+"rp=0.01//ohm per centimetre\n",
+"rs=2500//ohms\n",
+"j=5*10^-6\n",
+"//CALCULATIONS\n",
+"i=e/(rs+(lp*rp))\n",
+"p=i*rp*lp/100\n",
+"p1=p*ld\n",
+"T=p1/j\n",
+"t=(100*(et-e0))/(e100-e0)\n",
+"//results\n",
+"printf(' temperature= % 1f C',t)\n",
+"printf(' \n temperature= % 1f C',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.9: chapter_1_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"ht=65//cm\n",
+"h0=-5//cm\n",
+"t=273//c\n",
+"//CALCULATIONAS\n",
+"h100=h0+(100*(ht-h0)/t)\n",
+"l=(1+(t/273))\n",
+"H=(ht-(h0*l))/(l-1)\n",
+"printf(' temperature= % 1f cm',H)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/10-thermodynamic_relations.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/10-thermodynamic_relations.ipynb
new file mode 100644
index 0000000..ad4d23e
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/10-thermodynamic_relations.ipynb
@@ -0,0 +1,120 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 10: thermodynamic relations"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.13: chapter_10_example_13.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"dq=540000\n",
+"dv=1.676\n",
+"T1=373//k\n",
+"T2=423//k\n",
+"p1=1//pa\n",
+"//CALCULATIONS\n",
+"dt=T2-T1\n",
+"dp=(dt*dq*4.2)/(dv*T1)\n",
+"p2=p1+(dp/10^5)\n",
+"//results\n",
+"printf(' \n required pressure= % 1f pa',p2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.7: chapter_10_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"T=5+273//k\n",
+"v=10^-6//m3\n",
+"a=15*10^-6//k^-1\n",
+"cp=1005//cal/kg/k\n",
+"dp=(1000-0)*10^5//N/m2\n",
+"//CALCULATIONS\n",
+"dt=(T*a*v*dp)/(cp*4.2)\n",
+"//results\n",
+"printf(' \n temperature of water rises by= % 1f k',dt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.8: chapter_10_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"T=5+273//k\n",
+"v=10^-6//m3\n",
+"a=15*10^-6//k^-1\n",
+"cp=1005//cal/kg/k\n",
+"dp=(1000-0)*10^5//N/m2\n",
+"//CALCULATIONS\n",
+"q=(T*a*v*dp)/4.2\n",
+"//results\n",
+"printf(' \n quantity of heat given= % 1f cal',q)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/11-production_of_low_temperature.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/11-production_of_low_temperature.ipynb
new file mode 100644
index 0000000..54ce3bb
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/11-production_of_low_temperature.ipynb
@@ -0,0 +1,91 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 11: production of low temperature"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.2: chapter_11_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a=0.245\n",
+"b=2.67*10^-2\n",
+"dp=50//pa\n",
+"t1=300//k\n",
+"R=8.4//j\n",
+"//CALCULATIONS\n",
+"cp=7*R/5\n",
+"l=((2*a)/(R*t1))-b\n",
+"dt=(dp*l)/cp\n",
+"//results\n",
+"printf(' \n drop in temperature= % 1f k',dt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.3: chapter_11_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"k=6*10^-5\n",
+"B=5000\n",
+"c=420//J\n",
+"T=2//k\n",
+"//CALCULATIONS\n",
+"dt=-(k*B*B)/(2*c*T)\n",
+"T1=T+dt\n",
+"//results\n",
+"printf(' \n final temperature= % 1f k',T1)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/12-transmission_of_heat.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/12-transmission_of_heat.ipynb
new file mode 100644
index 0000000..83bcfc4
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/12-transmission_of_heat.ipynb
@@ -0,0 +1,418 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 12: transmission of heat"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.10: chapter_12_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"t2=162//c\n",
+"t1=62//c\n",
+"l=0.15//m\n",
+"d=0.02//m\n",
+"k=226//watt per kelvin metre\n",
+"//CALCULATIONS\n",
+"r=d/2\n",
+"a=3.14*r*r\n",
+"p=2*3.14*r\n",
+"x=(log(t2/t1))/l\n",
+"e=(x*x*k*a)/p\n",
+"//results\n",
+"printf(' \n surface emissivity of rod= % 1f ',e)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.11: chapter_12_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=5.6//c\n",
+"t2=2.8//c\n",
+"t3=0.7//c\n",
+"d1=2//m\n",
+"d2=4//m\n",
+"d3=8//m\n",
+"w=(2*3.14)/365\n",
+"//CALCULATIONS\n",
+"d=(log(t1/t2))/(d2/d1)\n",
+"k=w*1000/(d*d)\n",
+"//results\n",
+"printf(' \n diffusity= % 1f m^2 per day',k)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.12: chapter_12_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"kcu=0.93//cal per sec per cm per c\n",
+"t=700\n",
+"//CALCULATIONS\n",
+"khell=t*kcu\n",
+"kmks=khell*100\n",
+"ksi=4.2*khell\n",
+"//results\n",
+"printf(' \n conductivity= % 1f cal per sec per cm per c',khell)\n",
+"printf(' \n conductivity= % 1f cal per sec per m per c',kmks)\n",
+"printf(' \n conductivity= % 1f watt per m per k',ksi)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.1: chapter_12_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"cu=390\n",
+"al=226\n",
+"lal=0.05//m\n",
+"//CALCULATIONS\n",
+"lcu=((cu/al)^0.5)*lal\n",
+"//results\n",
+"printf(' \n wax melts up to= % 1f m',lcu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.2: chapter_12_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"m=96//gm\n",
+"m1=5//gm\n",
+"t1=37//c\n",
+"t2=10//c\n",
+"l=10//cm\n",
+"t=4*60//s\n",
+"a=5//cm^2\n",
+"dt=24//c\n",
+"//CALCULATIONS\n",
+"k=m*(t1-t2)/(a*t*dt)\n",
+"h1=m1*540\n",
+"h2=m*(t1-t2)\n",
+"dh=h1-h2\n",
+"p=dh*100/h1\n",
+"//results\n",
+"printf(' \n thermal conductivity= % 1f cgs units',k)\n",
+"printf(' \n percentage of heat loss= % 1f ',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.3: chapter_12_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"cu=90\n",
+"fe=12\n",
+"t1=200//c\n",
+"t2=0//c\n",
+"l=0.3//m\n",
+"a=5*10^-4//m^2\n",
+"//CALCULATIONS\n",
+"t=(t1*cu+fe*t2)/(cu+fe)\n",
+"dt=t1-t\n",
+"rh=cu*a*dt/0.15\n",
+"//results\n",
+"printf(' \n rate of heat flow= % 1f cal/sec',rh)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.4: chapter_12_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a=25//sq.mt\n",
+"aw=5//sq.mt\n",
+"dt=30//c\n",
+"t=60*60//sec\n",
+"l=0.3//m\n",
+"br=0.12\n",
+"gl=0.25\n",
+"l1=0.03//cm\n",
+"//CALCULATIONS\n",
+"A=4*a-aw\n",
+"hb=(br*A*dt*t)/(l*1000)\n",
+"hw=(gl*aw*dt*t)/(l1*100)\n",
+"tot=hb+hw\n",
+"//results\n",
+"printf(' \n total heat passing per hour= % 1f k.cal',tot)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.5: chapter_12_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"k1=0.252\n",
+"k2=0.05\n",
+"t1=273//k\n",
+"t2=285//k\n",
+"l1=0.0175//m\n",
+"l2=0.02//m\n",
+"//CALCULATIONS\n",
+"t=((k1/l1)*t1+(k2/l2)*t2)/(k1/l1+k2/l2)\n",
+"//results\n",
+"printf(' \n temperature of interface= % 1f k',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.6: chapter_12_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"cu=104\n",
+"w=0.14\n",
+"l1=50//cm\n",
+"t=0.0001//m\n",
+"t1=100//c\n",
+"t2=0//c\n",
+"//CALCULATIONS\n",
+"x=cu*t*100/w\n",
+"l=l1+2*x\n",
+"dt=t1-t2\n",
+"dg=dt/l\n",
+"d1=x*dg\n",
+"d2=t1-d1\n",
+"//results\n",
+"printf(' \n temperature gradient= % 1f c/cm',dg)\n",
+"printf(' \n  temperature of one end= % 1f c',d1)\n",
+"printf(' \n temperature of other end= % 1f c',d2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.7: chapter_12_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"m=4800//g\n",
+"lice=80//cal/g\n",
+"a=3600//sq.cm\n",
+"t1=100//c\n",
+"t2=0//c\n",
+"t=10//cm\n",
+"//CALCULATIONS\n",
+"h=(m*lice)/(a*t)\n",
+"dt=t1-t2\n",
+"k=(h*t)/(a*dt)\n",
+"//results\n",
+"printf(' \n thermal conductivity of stone= % 1f cal/cm s c',k)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.8: chapter_12_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=100//c\n",
+"t2=4//c\n",
+"k=0.5//cal/cm s c\n",
+"a=12//cm^2\n",
+"l=8//cm\n",
+"r=36//cal/s\n",
+"//CALCULATIONS\n",
+"T=(((r*l)/(k*a))+t1+t2)*0.5\n",
+"//results\n",
+"printf(' \n equilibrium temperature of inner surface= % 1f c',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.9: chapter_12_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"r2=0.5\n",
+"r1=0.4\n",
+"l=30//cm\n",
+"q=(500*10)/60\n",
+"t=100//c\n",
+"t1=20//c\n",
+"t2=30//c\n",
+"dt=t-(t1+t2)/2\n",
+"//CALCULATIONS\n",
+"k=(q*log((r2)/(r1)))/(2*3.14*dt*l)\n",
+"//results\n",
+"printf(' \n thermal conductivity of glass tube= % 1f cgs units',k)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/14-radiation_of_heat.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/14-radiation_of_heat.ipynb
new file mode 100644
index 0000000..71133d3
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/14-radiation_of_heat.ipynb
@@ -0,0 +1,381 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 14: radiation of heat"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.10: chapter_14_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"r=15*10^10//m\n",
+"R=7*10^8//m\n",
+"si=6.72*10^-8//j m^-2 sec^-1 deg^-4\n",
+"s=81350 //j m^-2 min^-1\n",
+"//CALCULATIONS\n",
+"t=(r*r*s)/(R*R*si*60)\n",
+"T=t^0.25\n",
+"//results\n",
+"printf(' \n value of temperature= % 1f k',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.11: chapter_14_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"s=8.2*10^4\n",
+"si=5.67*10^-8//j m^-2 sec^-1 deg ^-4\n",
+"a=32\n",
+"//CALCULATIONS\n",
+"r2=a/2\n",
+"r1=(r2*3.14)/(60*180)\n",
+"r=r1^2\n",
+"t=s/(r*60*si)\n",
+"T=t^0.25\n",
+"//results\n",
+"printf(' \n surface temperature of sun= % 1f k',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.12: chapter_14_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"s=1.5//cal cm^-2 min^-1\n",
+"k=0.0027\n",
+"//CALCULATIONS\n",
+"td=-(s/(k*60))\n",
+"//results\n",
+"printf(' \n temperature gradient= % 1f c cm^-1',td)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.1: chapter_14_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"si=5.735*10^-8//j m^-2 sec ^-1 deg^-4\n",
+"t=1227+273//k\n",
+"r=0.003//m\n",
+"//CALCULATIONS\n",
+"e=3.14*r*r*si*t^4*60/4.2\n",
+"//results\n",
+"printf(' \n energy= % 1f cal',e)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.2: chapter_14_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=573//k\n",
+"t2=273//k\n",
+"m=0.032//kg\n",
+"s=100\n",
+"r=0.35//c/sec\n",
+"a=0.0008//sq.mt\n",
+"e=1\n",
+"//CALCULATIONS\n",
+"E=m*s*r\n",
+"si=E/(a*e*((t1^4)-(t2^4)))\n",
+"//results\n",
+"printf(' \n stefans constant= % 1e j m^-2 sec^-1 deg^-4',si)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.3: chapter_14_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"E=40//j/sec\n",
+"a=0.66*10^-4//sq.mt\n",
+"e=0.31\n",
+"t=273+2170//k\n",
+"//CALCULATIONS\n",
+"si=E/(e*a*t^4)\n",
+"//results\n",
+"printf(' \n stefans constant= % 1e j m^-2 sec^-1 deg^-4',si)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.4: chapter_14_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=500//k\n",
+"t2=300//k\n",
+"m=10//kg\n",
+"s=100//cal/kg/k\n",
+"r=0.07//m\n",
+"//CALCULATIONS\n",
+"a=4*3.14*r*r\n",
+"E=a*((t1*t1*t1*t1)-(t2*t2*t2*t2))\n",
+"r=E/(m*s)\n",
+"//results\n",
+"printf(' \n maximum rate at which temperature will fall= % 1f c/sec',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.5: chapter_14_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=700//k\n",
+"t2=290//k\n",
+"E=10000//w m^-2\n",
+"si=5.7*10^-8\n",
+"//CALCULATIONS\n",
+"t=(t1^4+t2^4)/2\n",
+"T=t^0.25\n",
+"t1=E/si\n",
+"T1=t1^0.25\n",
+"//results\n",
+"printf(' \n temperature its rate will be halved= % 1f k',T)\n",
+"printf(' \n temperature of body= % 1f k',T1)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.6: chapter_14_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"E=40//w\n",
+"r=0.00005//m\n",
+"l=0.1//m\n",
+"si=5.67*10^-8\n",
+"T=2773//k\n",
+"//CALCULATIONS\n",
+"a=2*3.14*r*l\n",
+"e=E/(a*si*(T^4))\n",
+"//results\n",
+"printf(' \n relative emittance= % 1f ',e)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.7: chapter_14_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"r=0.02//m\n",
+"t1=120+273//k\n",
+"t2=100+273//k\n",
+"si=5.67*10^-8\n",
+"//CALCULATIONS\n",
+"a=4*3.14*r*r\n",
+"E=a*si*(t1^4-t2^4)\n",
+"//results\n",
+"printf(' \n rate at which energy must be supplied= % 1f watts',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.8: chapter_14_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t=6000//k\n",
+"r=17000\n",
+"//CALCULATIONS\n",
+"T=6000*17000^0.25\n",
+"//results\n",
+"printf(' \n temperature of the star= % 1f k',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.9: chapter_14_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"l=4753*10^-8//cm\n",
+"w=0.293\n",
+"t=10^7//k\n",
+"//CALCULATIONS\n",
+"T=w/l\n",
+"lm=w/(t*100)\n",
+"//results\n",
+"printf(' \n effective temperature of sun= % 1f k',T)\n",
+"printf(' \n wavelength of max energy= % 1e m',lm)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/15-elements_of_statistical_mechanics.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/15-elements_of_statistical_mechanics.ipynb
new file mode 100644
index 0000000..ce54bdf
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/15-elements_of_statistical_mechanics.ipynb
@@ -0,0 +1,328 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 15: elements of statistical mechanics"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.10: chapter_15_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=301//k\n",
+"t2=300//k\n",
+"f=5*(10^30)\n",
+"fa=f/2\n",
+"//CALCULATIONS\n",
+"r=t1/t2\n",
+"i=r^fa\n",
+"//results\n",
+"printf(' \sigma(E) increases by a factor r^fa ')\n",
+"printf(' \n r= % 1f ',r)\n",
+"printf(' \n fa= % 1f ',fa)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.11: chapter_15_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"de=5.52*10^-21//j\n",
+"k=1.38*10^-23\n",
+"//CALCULATIONS\n",
+"t=de/(2*k)\n",
+"//results\n",
+"printf(' \n temperature of system= % 1f k',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.14: chapter_15_example_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p=0.76*9.81*13600\n",
+"dv=10^-5//m3\n",
+"k=1.38*10^-23\n",
+"t=300//k\n",
+"//CALCULATIONS\n",
+"r=(p*dv)/(k*t)\n",
+"//results\n",
+"printf(' \n factor by which number of accessible states increases is exp(r) ')\n",
+"printf(' \n r= % 1e ',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.1: chapter_15_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"c=8\n",
+"h=3\n",
+"t=5\n",
+"//CALCULATIONS\n",
+"a=factorial(8)/(factorial(3)*factorial(5)*2^8)\n",
+"//results\n",
+"printf(' \n probability of 3 heads and 5 tails= % 1f ',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.2: chapter_15_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=5\n",
+"h=2\n",
+"p=1/6\n",
+"//CALCULATIONS\n",
+"t=1-p\n",
+"a=((factorial(n))/(factorial(h)*factorial(n-h)))*(p^h)*(t^(n-h))\n",
+"//results\n",
+"printf(' \n probability of apperance of 4 in two dices= % 1f ',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.3: chapter_15_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=12\n",
+"p=2\n",
+"//CALCULATIONS\n",
+"t=n/p\n",
+"a=factorial(n)/(factorial(t)*factorial(n-t)*p^n)\n",
+"//results\n",
+"printf(' \n probability= % 1f ',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.4: chapter_15_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=10\n",
+"a=0.6\n",
+"h=0\n",
+"//CALCULATIONS\n",
+"b=1-a\n",
+"p=factorial(n)*a^10/(factorial(n-h)*factorial(h))\n",
+"//results\n",
+"printf(' \n probability of heads occurence= % 1f ',a*10)\n",
+"printf(' \n probability of occuring head only in 10 throws= % 1f ',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.5: chapter_15_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=400\n",
+"a1=300\n",
+"b1=100\n",
+"a2=200\n",
+"b2=200\n",
+"r=2\n",
+"//CALCULATIONS\n",
+"p1=factorial(n)/(factorial(a1)*factorial(b1)*r^n)\n",
+"p2=factorial(n)/(factorial(a2)*factorial(b2)*r^n)\n",
+"w=p1/p2\n",
+"//results\n",
+"printf(' \n ratio of probabilities= % 1e ',w)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.6: chapter_15_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a1=2\n",
+"a2=6\n",
+"a3=16\n",
+"a4=2\n",
+"b1=1\n",
+"b2=3\n",
+"b3=4\n",
+"b4=7\n",
+"//CALCULATIONS\n",
+"a=a1+a2+a3+a4\n",
+"x=a1*b1+a2*b2+a3*b3+a4*b4\n",
+"p2=a1/a\n",
+"p6=a2/a\n",
+"p16=a3/a\n",
+"d=x/a\n",
+"//results\n",
+"printf(' \n probability of state 2= % 1f ',p2)\n",
+"printf(' \n probability of state 6= % 1f ',p6)\n",
+"printf(' \n probability of state 16= % 1f ',p16)\n",
+"printf(' \n value of <x>= % 1f ',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.9: chapter_15_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"dx=10^-11//m\n",
+"c=10^7//m/sec\n",
+"h=6.6*10^-34\n",
+"//CALCULATIONS\n",
+"dp=(9.1*10^-31*c)\n",
+"n=(2*dx*dp*100)/h\n",
+"//results\n",
+"printf(' \n number of quantum states available= % 1f ',n)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/16-classical_and_quantum_statistics.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/16-classical_and_quantum_statistics.ipynb
new file mode 100644
index 0000000..f6f73d5
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/16-classical_and_quantum_statistics.ipynb
@@ -0,0 +1,144 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 16: classical and quantum statistics"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.10: chapter_16_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t=300//k\n",
+"e=0.01//v\n",
+"//CALCULATIONS\n",
+"a=1/((exp(e/t))+1)\n",
+"//results\n",
+"printf(' \n NFD= % 1f ',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.11: chapter_16_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=6.06*10^26\n",
+"p=2.7*10^3\n",
+"h=6.6*10^-34\n",
+"m=9.1*10^-31//kg\n",
+"gs=2\n",
+"ml=26.98*10^-3\n",
+"//CALCULATIONS\n",
+"a=(h*h/(2*m*100))*((3*3*n*p/(4*3.14*gs*ml))^(2/3))\n",
+"r=a/(1.609*10^-19)\n",
+"//results\n",
+"printf(' \n fermi energy= % 1f ev',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.2: chapter_16_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"h=6.6*10^-34\n",
+"c=3*10^8//m/sec\n",
+"k=1.38*10^-23\n",
+"t=1000//k\n",
+"//CALCULATIONS\n",
+"l=(h*c)/(5*k*t)\n",
+"///results\n",
+"printf(' \n wavelength associated with maximum radiation= % 1e ',l)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.5: chapter_16_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"h=6.6*10^-34//j sec\n",
+"r=5.86*10^28\n",
+"m=9.1*10^-31//kg\n",
+"gs=2\n",
+"//CALCULATIONS\n",
+"a=(h*h/(2*m))*((3*r/(4*3.14*gs))^(2/3))\n",
+"//resullts\n",
+"printf(' \n fermi energy= % 1e',a)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/2-Thermal_Expansion.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/2-Thermal_Expansion.ipynb
new file mode 100644
index 0000000..8289be5
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/2-Thermal_Expansion.ipynb
@@ -0,0 +1,326 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 2: Thermal Expansion"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.10: chapter_2_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"ym=1.8*10^-4\n",
+"yg=2.5*10^-5\n",
+"//CALCULATIONS\n",
+"s=yg/ym\n",
+"//results\n",
+"printf(' volume of vessel to be filled= % 1f 1/C',s)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.12: chapter_2_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"l=1//m\n",
+"ld1=0.7//m\n",
+"ld2=0.78//m\n",
+"d1=0\n",
+"d2=30\n",
+"vd1=l-(ld1*cosd(d1))\n",
+"vd2=l-(ld2*cosd(d2))\n",
+"//CALCULATIONS\n",
+"H=((ld1*vd1)-(ld2*vd2))/(vd1-vd2)\n",
+"//results\n",
+"printf(' atmospheric pressure= % 1f m',H)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.13: chapter_2_example_13.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"r=1/1.035\n",
+"t1=15//c\n",
+"t2=25//c\n",
+"//CALCULATIONS\n",
+"x=-(t1-(t2*r))/(r-1)\n",
+"//results\n",
+"printf(' absolute zero on celsius scale for this gas= % 1f c',x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.14: chapter_2_example_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p=0.76\n",
+"t1=0//c\n",
+"t2=100//c\n",
+"T1=t1+273//k\n",
+"T2=t2+273//k\n",
+"//CALCULATIONS\n",
+"p=(2*p*T2)/(T1+T2)\n",
+"//results\n",
+"printf(' pressure of the gas= % 1f m',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.15: chapter_2_example_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"s=0.00018//1/c\n",
+"dt=1//c\n",
+"//CALCULATIONS\n",
+"p=(s*dt)*100\n",
+"//results\n",
+"printf(' percentage change= % 1f',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.5: chapter_2_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=0//c\n",
+"t2=20//c\n",
+"g=0.000011//1/c\n",
+"h=0.000019//1/c\n",
+"l=41.628//cm\n",
+"//CALCULATIONS\n",
+"l20=l*(1+(h*(t2-t1)))\n",
+"l0=l20/(1+(g*(t2-t1)))\n",
+"//results\n",
+"printf(' true length of rod at 20 c= % 1f C',l20)\n",
+"printf(' true length of rod at 0 c= % 1f C',l0)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.6: chapter_2_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"l=3//m\n",
+"t1=0//c\n",
+"t2=40//c\n",
+"f=0.000012//1/c\n",
+"b=0.000018//1/c\n",
+"y=2.1*10^11//N/m^2\n",
+"a=(3.14*(0.6*10^-3)^2)/4///m\n",
+"//CALCULATIONS\n",
+"lb40=l*(1+(b*(t2-t1)))\n",
+"lf40=l*(1+f*(t2-t1))\n",
+"dl=lb40-lf40\n",
+"F=y*a*dl*0.01/l\n",
+"//results\n",
+"printf(' extra tension of the wire= % 1f newton',F)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.7: chapter_2_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"l20=0.1//m\n",
+"l1=0.0999//m\n",
+"s=0.000011//1/c\n",
+"t1=20\n",
+"//CALCULATIONS\n",
+"t=((l1-l20)/(l20*s))+20\n",
+"//results\n",
+"printf(' temperature the rod must be reduced is= % 1f C',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.8: chapter_2_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"s=1.9*10^-5//1/c\n",
+"t1=15//c\n",
+"t2=20//c\n",
+"//CALCULATIONS\n",
+"g=(1+(s*(t2-t1)))^(0.5)\n",
+"h=g-1\n",
+"d=h*24*60*60\n",
+"//results\n",
+"printf(' per day difference= % 1f sec',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.9: chapter_2_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"e=6000*10^-10//m\n",
+"p=25\n",
+"l=1.5*10^-2\n",
+"t2=40\n",
+"t1=0\n",
+"sx=13*10^-7//1/c\n",
+"sy=231*10^-7//1/c\n",
+"sz=231*10^-7//1/c\n",
+"//CALCULATIONS\n",
+"s=((p*e)/(2*l*(t2-t1)))\n",
+"y=sx+sy+sz\n",
+"//results\n",
+"printf(' alpha of crystal= % 1f 1/C',s)\n",
+"printf(' coefficient of cubical expansion= % 1f 1/C',y)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/3-calorimetry.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/3-calorimetry.ipynb
new file mode 100644
index 0000000..21b416d
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/3-calorimetry.ipynb
@@ -0,0 +1,554 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 3: calorimetry"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.10: chapter_3_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"m1=250//gm\n",
+"m2=200//gm\n",
+"l=336//j\n",
+"w1=50//gm\n",
+"m3=200//gm\n",
+"t1=100//c\n",
+"//calculations\n",
+"M1=m1+m2+w1\n",
+"J=t1*M1*4.2\n",
+"k=l*m2\n",
+"m=123.2\n",
+"T=m1+m3+m\n",
+"//results\n",
+"printf(' total contents= % 1f gm',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.12: chapter_3_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"m1=10//kg\n",
+"t1=80//c\n",
+"t2=20//c\n",
+"t3=150//c\n",
+"t4=90//c\n",
+"t=100//c\n",
+"a=800//cal/kg\n",
+"//calculations\n",
+"h=m1*1000*(t1-t2)/1000\n",
+"H=a*(t3-t)+540000+1000*(t-t4)\n",
+"k=H/1000\n",
+"x=h/k\n",
+"//results\n",
+"printf(' kg of steam required per hour= % 1f kg/hr',x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.13: chapter_3_example_13.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p1=6//atm\n",
+"p2=2//atm\n",
+"ph=89//kg/m^3\n",
+"v=30/1000//ml\n",
+"t1=10//c\n",
+"t3=31.5//c\n",
+"T1=273+t1\n",
+"t2=150//c\n",
+"w1=0.210//kg\n",
+"//calculations\n",
+"m=(p1-p2)*273*ph*v/(T1*1000)\n",
+"t4=(t1+t3)/2\n",
+"h=m*(t2-t4)\n",
+"H=w1*1000*4.18*(t3-t1)\n",
+"c=H/h\n",
+"//results\n",
+"printf(' specific heat= % 1f j/kg*k',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.14: chapter_3_example_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"po=101396.1\n",
+"p=1.293\n",
+"vo=1/p\n",
+"t=273\n",
+"cp=961.4\n",
+"//calculations\n",
+"R=po*vo/t\n",
+"cv=cp-R\n",
+"//results\n",
+"printf(' specific heat at constant volume= % 1f',cv)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.15: chapter_3_example_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"m=5//kg\n",
+"m1=2.09*10^8\n",
+"val=10^7//cal/kg\n",
+"p=0.12\n",
+"//calculations\n",
+"w=p*m1/(60*60)\n",
+"H=w/746\n",
+"//results\n",
+"printf(' average horse power= % 1f',H)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.16: chapter_3_example_16.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"po=101396.16//N/m^2\n",
+"vo=22.4//l\n",
+"t=273\n",
+"m=4*1000//gm\n",
+"//calculations\n",
+"R=po*vo/t\n",
+"c=R/m\n",
+"//results\n",
+"printf(' pressure of the gas= % 1f j',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.17: chapter_3_example_17.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p1=1\n",
+"p2=0.8\n",
+"t1=25//c\n",
+"t2=10//c\n",
+"p=0.4\n",
+"t3=61//c\n",
+"t4=12//c\n",
+"//calculations\n",
+"p1=p*(t3-t4)\n",
+"m=(t1-t2)\n",
+"c=m/p1\n",
+"//results\n",
+"printf(' specific heat of liquid= % 1f cal/gm*c',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.19: chapter_3_example_19.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p16=80//cm\n",
+"v16=432//cc\n",
+"t=273//k\n",
+"po=76//cm\n",
+"t=16//c\n",
+"t16=273+t//k\n",
+"T=273//k\n",
+"poxy=0.0014\n",
+"cfe=0.09\n",
+"t1=15//c\n",
+"t2=184//c\n",
+"m1=2//gm\n",
+"//calculations\n",
+"v0=(p16*v16*T)/(po*t16)\n",
+"m=poxy*v0\n",
+"h=m1*cfe*(t1+t2)\n",
+"l=h/m\n",
+"//results\n",
+"printf(' latent heat= % 1f cal',l)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.2: chapter_3_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"cag=56\n",
+"cpb=31\n",
+"cal=220\n",
+"//CALCULATIONS\n",
+"mag=1000/cag\n",
+"mpb=1000/cpb\n",
+"mal=1000/cal\n",
+"//results\n",
+"printf(' mass of silver= % 1f kg',mag)\n",
+"printf(' mass of lead= % 1f kg',mpb)\n",
+"printf(' mass of aluminium= % 1f kg',mal)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.3: chapter_3_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"m1=0.5//kg\n",
+"m2=0.09//kg\n",
+"t1=19//c\n",
+"t2=15//c\n",
+"t3=38//c\n",
+"t4=50//c\n",
+"s=1000\n",
+"//CALCULATIONS\n",
+"A=[4000 -15.5; 23000 11.5]\n",
+"b=[-360;1080]\n",
+"c=A\b\n",
+"R1=c(1,1)\n",
+"R2=c(2,1)\n",
+"//results\n",
+"printf(' water equivalent of mercury= % 1f kg',R1)\n",
+"printf(' \n specific heat of mercury= % 1f c /kg/c',R2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.4: chapter_3_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"c=10^6//calories\n",
+"tw=100//sec\n",
+"ta=74//sec\n",
+"dw=1000//kg/m^3\n",
+"da=800//Kg/m^3\n",
+"t2=50//c\n",
+"t1=40//c\n",
+"//CALCULATIONS\n",
+"hw=((dw*1000*10)+(c*(t2-t1)))\n",
+"rw=hw/tw\n",
+"C=(((rw*ta)/(t2-t1))-c)/da\n",
+"printf(' specific heat of alcohol= % 1f calories/kg',C)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.5: chapter_3_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"mc=0.1//kg\n",
+"vl1=150//cc\n",
+"vl2=150//cc\n",
+"hl1=600\n",
+"gl1=1200\n",
+"hl2=400\n",
+"gl2=900\n",
+"t1=50//c\n",
+"t2=40//c\n",
+"sc=100\n",
+"r1=2\n",
+"//CALCULATIIONS\n",
+"m1=vl1*gl1/(10^6)\n",
+"rc1=(m1*hl1+mc*sc)*r1\n",
+"k= -rc1/t1\n",
+"m2=vl2*gl2/(10^6)\n",
+"b=(m2*hl2+mc*sc)\n",
+"j=-k*t2\n",
+"//results\n",
+"printf(' rate of cooling= % 1f cal/min',j)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.6: chapter_3_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialistions\n",
+"t1=80//c\n",
+"t2=50//c\n",
+"t3=60//c\n",
+"t4=30//c\n",
+"t=20\n",
+"e=5\n",
+"//CALCULATIONS\n",
+"k=2.3026*log((t1-t)/(t2-t))/e\n",
+"T=2.3026*log((t3-t)/(t4-t))/k\n",
+"//results\n",
+"printf(' time it will take = % 1f min',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.7: chapter_3_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"e=1.586//v\n",
+"i=0.1444//amp\n",
+"t=4*60//sec\n",
+"m=0.3963//kg\n",
+"T=1.219//k\n",
+"wt=206.4\n",
+"//CALCULATIONS\n",
+"hg=e*i*t\n",
+"c=hg/(m*T*4.18)\n",
+"a=c*wt\n",
+"printf(' atomic heat of lead= % 1f 1/k',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.8: chapter_3_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation if variables\n",
+"m=1*10^-4//kg\n",
+"v=0.0005//m^3\n",
+"l=22.57*10^5//j\n",
+"t1=15//c\n",
+"p=6//kg/m^3\n",
+"//calculations\n",
+"H=m*l\n",
+"h=v*p*(100-t1)*4.18\n",
+"c=H/h\n",
+"//results\n",
+"printf(' specific heat of gas at constant volume= % 1f j',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.9: chapter_3_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"j1=21*10^5//j\n",
+"j2=3.36*10^5//j\n",
+"//calculations\n",
+"x=j1*100/(j1+j2)\n",
+"//results\n",
+"printf(' percentage of water present will be frozen= % 1f',x)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/4-change_of_state.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/4-change_of_state.ipynb
new file mode 100644
index 0000000..fb620ae
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/4-change_of_state.ipynb
@@ -0,0 +1,427 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 4: change of state"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.10: chapter_4_exampe_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"r=52\n",
+"svp=17.5//mm\n",
+"//CALCULATIONS\n",
+"p=(svp*r)/100\n",
+"//results\n",
+"printf(' SVP at dew point= % 1f mm',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.12: chapter_4_exampe_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p=4.60//mm\n",
+"p1=0.34//mm\n",
+"t=0.007//c\n",
+"r=760//mm\n",
+"//CALCULATIONS\n",
+"P=(p+(p1*t))\n",
+"fp=r-P\n",
+"d=r*t/fp\n",
+"//results\n",
+"printf(' lowering of melting point of ice= % 5f C',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.14: chapter_4_exampe_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"v2=1.677//m3\n",
+"v1=0.001//m3\n",
+"dp=0.76*13600*9.81\n",
+"t=100//c\n",
+"T=t+273//k\n",
+"L=540000//cal//kg\n",
+"//CALCULATIONS\n",
+"dT=(dp*T*(v2-v1))/L\n",
+"//results\n",
+"printf(' increase in boiling point= % 1f C',dT)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.15: chapter_4_exampe_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=18//c\n",
+"t2=19//c\n",
+"t3=18.6//c\n",
+"t4=23//c\n",
+"t5=24//c\n",
+"t6=23.7//c\n",
+"svp1=15.46//mm\n",
+"svp2=16.46//mm\n",
+"svp4=21.02//mm\n",
+"svp5=22.32//mm\n",
+"//CALCULATIONS\n",
+"svp3=svp1+((svp2-svp1)/(t2-t1))\n",
+"svp6=svp4+((svp4-svp5)/(t4-t5))\n",
+"rh=svp3*100/svp6\n",
+"//results\n",
+"printf(' relative humidity= % 1f ',rh)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.2: example_4_chapter_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"t1=20//c\n",
+"m1=10//gm\n",
+"t2=-80//c\n",
+"t2=15//c\n",
+"m2=10.77//gm\n",
+"t3=10//c\n",
+"c=0.5\n",
+"//CALCULATIONS\n",
+"A=[5 -10;5 -10.77]\n",
+"b=[550;488.5]\n",
+"c=A\b\n",
+"R1=c(1,1)\n",
+"R2=c(2,1)\n",
+"//results\n",
+"printf(' latent heat of fusion of ice= %1f cal/gm',R2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.3: chapter_4_exampe_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"c=0.58\n",
+"m=4//gm\n",
+"ms=5//gm\n",
+"t=78//c\n",
+"t1=80//c\n",
+"x1=10//cm\n",
+"x2=8.5//cm\n",
+"c1=0.05\n",
+"c2=0.048\n",
+"t2=100//c\n",
+"t3=27//c\n",
+"//CALCULATIONS\n",
+"Hal=m*c*t\n",
+"m1=Hal/t1\n",
+"m2=m1*x1/x2\n",
+"Hp=m2*80\n",
+"H1=ms*(t2-t3)*c1\n",
+"H2=ms*c2*t3\n",
+"L=(Hp-H1-H2)/ms\n",
+"//results\n",
+"printf(' latent heat of fusion= % 1f cal/gm',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.4: chapter_4_exampe_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"d=2*10^-3//m\n",
+"x=0.07//m\n",
+"m1=2.2*10^-3//gm\n",
+"pice=920//kgm^-3\n",
+"pwater=1000//kgm^-3\n",
+"lice=80000//cal/kg\n",
+"//CALCULATIONS\n",
+"a=22*d*d/(4*7)\n",
+"v=x*a\n",
+"v1=1/pice\n",
+"v2=1/pwater\n",
+"dv=v1-v2\n",
+"m2=v/dv\n",
+"h=lice*m2\n",
+"L=h/m1\n",
+"printf(' latent heat of vapourisation= % 2f cal/kg',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.5: chapter_4_exampe_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"ms=0.0055//kg\n",
+"t1=100//c\n",
+"t2=15//c\n",
+"t3=26.8//c\n",
+"m1=250/1000//kg\n",
+"m2=16.2/1000//kg\n",
+"l=22.572*10^5//kg\n",
+"//calculations\n",
+"h=(m1+m2)/(t3-t2)\n",
+"x=(h-(ms*l))/(t1-t3-l)\n",
+"p=x*100/ms\n",
+"//results\n",
+"printf(' perecntage of water in steam= % 5f ',x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.6: chapter_4_exampe_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//intialisation\n",
+"r=1.7*10^-6//m^3/sec\n",
+"t1=3.56//c\n",
+"pw=1000//kg/m^3\n",
+"r1=0.34*10^-6//m^3/sec\n",
+"t2=15//c\n",
+"bp=360//c\n",
+"c=33\n",
+"pl=13600//kg/m^3\n",
+"//CALCCULATIONS\n",
+"m=r*pw*60\n",
+"h1=m*1000*t1\n",
+"h2=r1*pl*(bp-t2)*c\n",
+"L=(h1-h2)/(r1*pl)\n",
+"//results\n",
+"printf(' latent heat of vaporisation= % 1f cal/kg',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.7: chapter_4_exampe_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p1=75.5//cm\n",
+"v1=123//cc\n",
+"t0=273//k\n",
+"t1=15//c\n",
+"T1=t0+t1\n",
+"p0=76//cm\n",
+"r=1.43//gm/litre\n",
+"l=51//cal/gm\n",
+"t2=-183//c\n",
+"m=0.495//gm\n",
+"//calculations\n",
+"v0=p1*v1*t0/(p0*T1)\n",
+"h=r*v0*l/1000\n",
+"c=(h/(m*(t1-t2)))\n",
+"//results\n",
+"printf(' mean specific heat = % 1f calC/gm/deg',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.8: chapter_4_exampe_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p=0.76\n",
+"v=1650//cc\n",
+"m=1//gm\n",
+"r=13600//kg/m3\n",
+"//CALCULATIONS\n",
+"w=(p*9.81*r*(v-1)*10^-6)/4.18\n",
+"ih=540-w\n",
+"//results\n",
+"printf(' internal latent heat of steam= % 1f cal',ih)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.9: chapter_4_exampe_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"x1=17.5//mm\n",
+"x2=9.2//mm\n",
+"r=0.7\n",
+"//CALCULATIONS\n",
+"avp=x1*r\n",
+"dsvp=avp-x2\n",
+"f=dsvp*100/avp\n",
+"//results\n",
+"printf(' fraction of water vapour condensed= % 1f ',f)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/5-Kinetic_theory_of_Heat.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/5-Kinetic_theory_of_Heat.ipynb
new file mode 100644
index 0000000..7529df9
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/5-Kinetic_theory_of_Heat.ipynb
@@ -0,0 +1,152 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 5: Kinetic theory of Heat"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.1: chapter_5_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"h=50//m\n",
+"g=9.8//m/sec2\n",
+"l=1000\n",
+"j=4.2//j/cal\n",
+"//calculations\n",
+"q=h*g/j\n",
+"t=q/l\n",
+"//results\n",
+"printf(' difference in temperature of water= % 1f C',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.2: chapter_5_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"t1=327//c\n",
+"t2=47.6//c\n",
+"c=30//cal/kg\n",
+"l=6000//cal/kg\n",
+"j=4.2//j/cal\n",
+"//CALCULATIONS\n",
+"h=c*(t1-t2)+l\n",
+"v=sqrt(2*j*h)\n",
+"//results\n",
+"printf(' velocity of bullet= % 1f m/sec',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.3: chapter_5_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"e=3//v\n",
+"i=2//amp\n",
+"e1=3.75//v\n",
+"i1=2.5//amp\n",
+"t=2//c\n",
+"m=30//gm/min\n",
+"m1=48//gm/min\n",
+"//CALCULATIONS\n",
+"p=(e*i-e1*i1)/(t*(m-m1)/44.444)\n",
+"//results\n",
+"printf(' J= % 1f j/cal',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.4: chapter_5_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"c=1000\n",
+"t=1//c\n",
+"f=1//f\n",
+"J=4.18//j/cal\n",
+"g=9.8//m/sec2\n",
+"//CALCULATIONS\n",
+"h=c*t*J/g\n",
+"h1=h*f*5/9\n",
+"//results\n",
+"printf(' height pf waterfall to rasie 1 c= % 1f m',h)\n",
+"printf(' height of waterfall to raise 1 f= % 1f m',h1)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/6-kinetic_theory_of_gases.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/6-kinetic_theory_of_gases.ipynb
new file mode 100644
index 0000000..7cf1014
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/6-kinetic_theory_of_gases.ipynb
@@ -0,0 +1,448 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 6: kinetic theory of gases"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.10: chapter_6_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"r=8.3//j/mol/k\n",
+"J=4.2//j/cal\n",
+"T=273\n",
+"m=2//gm\n",
+"//CALCULATIONS\n",
+"ke=(3*r*T/(2*m*J))\n",
+"//results\n",
+"printf(' ke of one gm of hydrogen= % 1f calories',ke)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.11: chapter_6_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p0=0.76*13600*9.81\n",
+"m=1.785*10^-4//kg\n",
+"v0=0.001/m\n",
+"T0=273//k\n",
+"g=1.67\n",
+"cp=1250\n",
+"//CALCULATIONS\n",
+"r=p0*v0/T0\n",
+"J=r*g/((g-1)*cp)\n",
+"//results\n",
+"printf(' mechanical equivalent of heat= % 1f joules/cal',J)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.12: chapter_6_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=1.7*10^-5//newton/m2/unit vel gradient\n",
+"p=10^5//newton//m2\n",
+"d=1.2//kg/m3\n",
+"//CALCULATIONS\n",
+"l=n*sqrt(3/(d*p))\n",
+"f=p/n\n",
+"//results\n",
+"printf('.mean free path= % 1e m',l)\n",
+"printf(' \ncollision frequency= % 1f per second',f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.13: chapter_6_example_13.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=166*10^-7//kg/m/sec\n",
+"k=2.7*10^25//m^-3\n",
+"d=1.25//kg/m^3\n",
+"c=450//m/sec\n",
+"//CALCULATIONS\n",
+"l=3*n/(d*c)\n",
+"f=c/l\n",
+"di=sqrt(1/(sqrt(2)*%pi*k*l))\n",
+"//results\n",
+"printf(' mean free path= % 1e m',l)\n",
+"printf(' \ncollision frequency= % 1e c',f)\n",
+"printf(' \navg velocity= % 1e m',di)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.14: chapter_6_example_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"m=40//kg\n",
+"v=22.4//m^-3\n",
+"n=2.1*10^-5\n",
+"r=8314//j/mol/k\n",
+"T=273//k\n",
+"//CALCULATIONS\n",
+"d=m/v\n",
+"c=sqrt(3*r*T/m)\n",
+"l=(3*n)/(d*c)\n",
+"f=c/l\n",
+"//results\n",
+"printf(' mean freepath= % 1e m',l)\n",
+"printf(' \ncollision frequency= % 1f ',f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.15: chapter_6_example_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"l1=23*10^-6\n",
+"l0=19*10^-6\n",
+"d=0.1785\n",
+"p=10^5//n\n",
+"//CALCULATIONS\n",
+"df=(l1-l0)*sqrt(3/(p*d))/0.4\n",
+"//results\n",
+"printf(' difference in mean free path= % 1e m',df)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.19: chapter_6_example_19.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"f=5\n",
+"r=2\n",
+"//CALCULATIONS\n",
+"e=f/2\n",
+"g=r/2\n",
+"p=g*100/e\n",
+"//results\n",
+"printf(' fraction used to increase rotational energy= % 1f ',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.20: chapter_6_example_20.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"s1=1//m/sec\n",
+"s2=2//m/sec\n",
+"s3=3//m/sec\n",
+"s4=4//m/sec\n",
+"s5=5//m/sec\n",
+"n1=4\n",
+"n2=2\n",
+"n3=8\n",
+"n4=6\n",
+"n5=5\n",
+"//CALCULATIONS\n",
+"u=(n1*s1+n2*s2+n3*s3+n4*s4+n5*s5)/(n1+n2+n3+n4+n5)\n",
+"v=sqrt((n1*s1*s1+n2*s2*s2+n3*s3*s3+n4*s4*s4+n5*s5*s5)/(n1+n2+n3+n4+n5))\n",
+"//results\n",
+"printf(' mean speed of molecules= % 1f m/sec',u)\n",
+"printf(' \nrms speeed of molecules= % 1f m/sec',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.2: chapter_6_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"n=3\n",
+"r=2\n",
+"//CALCULATIONS\n",
+"i=3*n-3\n",
+"v=i-r\n",
+"//results\n",
+"printf(' vibratory degree of freedom= % 1f ',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.5: chapter_6_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"T=273//k\n",
+"m=35.5//kg\n",
+"r=8314.3//j/mol/k\n",
+"//CALCULATIONs\n",
+"c=sqrt(3*T*r/(2*m))\n",
+"//results\n",
+"printf(' rms velocity = % 1f m/sec',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.6: chapter_6_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"m=2//kg\n",
+"T=273//k\n",
+"r=8314.3//j/mol/k\n",
+"//CALCULATIONS\n",
+"c=sqrt(3*r*T/m)\n",
+"Ti=(4*c*c*m/(3*r))\n",
+"C=Ti-273\n",
+"//results\n",
+"printf(' temperature at which rms speed will double is= % 1f c',C)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.7: chapter_6_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p=1.013*10^5//newton/m2\n",
+"d=0.09//kg/m3\n",
+"t1=27//c\n",
+"T=273\n",
+"T1=t1+T//k\n",
+"//CALCULATIONS\n",
+"c1=sqrt(3*p/d)\n",
+"c2=c1*sqrt(T1/T)\n",
+"cb=c2*8/(3*%pi)\n",
+"cm=c2*sqrt(2/3)\n",
+"//results\n",
+"printf(' avg velocity= % 1f m/sec',cb)\n",
+"printf(' \nmost probable velocity= % 1f m/sec',cm)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.8: chapter_6_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisations\n",
+"e=4*10^-3//erg\n",
+"p=1*13.6*981\n",
+"//calculations\n",
+"kt=2*e/3//erg\n",
+"n=p/kt\n",
+"//results\n",
+"printf(' number of molecules = % 1f',kt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.9: chapter_6_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"r=8.32//j/mol/k\n",
+"N=6.06*10^23\n",
+"t=723\n",
+"T=t+273\n",
+"//calculations\n",
+"ke=(3*r*T)/(2*N)\n",
+"ke1=ke*N\n",
+"//results\n",
+"printf(' mean translational kinetic energy= % 1f J',ke1)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/7-continuity_of_state.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/7-continuity_of_state.ipynb
new file mode 100644
index 0000000..d55c7df
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/7-continuity_of_state.ipynb
@@ -0,0 +1,285 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 7: continuity of state"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.10: chapter_7_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"m=2*10^-3//kg\n",
+"R=8.31//j/mol/k\n",
+"p=2*10^5\n",
+"v=8.2*10^-4\n",
+"a=0.136//pa m^6\n",
+"M=28*10^-3//kg/\n",
+"//CALCULATIONS\n",
+"t=(p*v*M)/(R*m)\n",
+"T=(M/(m*R))*(p+(m*m*a/(M*M*v*v)))*(v-(m*b/M))\n",
+"//results\n",
+"printf(' \n temperature for a perfect gas= % 1f k',t)\n",
+"printf(' \n temperature for vanderwaals gas= % 1f k',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.11: chapter_7_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a=0.132//nm^4/mole^2\n",
+"b=3.12*10^-5//m^3/mole^2\n",
+"p=5*10^5//Nm^-2\n",
+"v=20*10^-3//m3\n",
+"R=8.4//j/mole/k\n",
+"v2=2*10^-3//m3\n",
+"p1=5//pa\n",
+"//CALCULATIONS\n",
+"t=((p+(a/(v*v)))*(v-b))/(5*R)\n",
+"p2=(p1*v)/v2\n",
+"//results\n",
+"printf(' \n temperature = % 1f k',t)\n",
+"printf(' \n pressure= % 1f pa',p2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.12: chapter_7_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"t1=273//k\n",
+"p1=1*10^5//N/m2\n",
+"p2=2*10^5//N/m2\n",
+"v=10^-6//m3\n",
+"a=2.73*10^-10//m4 N\n",
+"b=1.03*10^-9//m3\n",
+"//CALCULATIONS\n",
+"t2=t1+(t1*(p2-p1))/(p1+(a/(v*v)))\n",
+"//results\n",
+"printf(' \n temperature of gas if pressure is doubled= % 1f k',t2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.1: chapter_7_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"R=82.07//cm3.atmos.per k\n",
+"t=132//k\n",
+"p=37.2//atm\n",
+"//CALCULATIONS\n",
+"a=(27*R*R*t*t)/(64*p)\n",
+"b=(R*t)/(8*p)\n",
+"//results\n",
+"printf(' a= % 1f atmos cm ^6',a)\n",
+"printf(' \nb= % 1f cm^3',b)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.2: chapter_7_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"p=2.26//atmos\n",
+"m=1.014*10^6*4\n",
+"R=8.3*10^7\n",
+"d=0.069//gm/cm3\n",
+"//CALCULATIONS\n",
+"t=(8*p*m)/(3*R*d)\n",
+"//results\n",
+"printf(' critical temperature of helium= % 1f K',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.7: chapter_7_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a=0.0072\n",
+"b=0.002\n",
+"p=1\n",
+"v=1\n",
+"t=273//k\n",
+"//CALCULATIONS\n",
+"R=((p+(a/(v*v)))*(v-b))/t\n",
+"Tc=(8*a)/(27*R*b)\n",
+"TC=Tc-t\n",
+"Tb=3.375*Tc\n",
+"TB=Tb-t\n",
+"//results\n",
+"printf(' critical temperature of Co2= % 1f c',TC)\n",
+"printf(' \nboyle temperature of Co2= % 1f k',Tb)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.8: chapter_7_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a=0.0072//pa cc^2\n",
+"b=0.002\n",
+"p1=76*13.6*980\n",
+"p2=0.76*13600*9.8\n",
+"//CALCULATIONS\n",
+"a1=a*p2/p1\n",
+"//results\n",
+"printf(' value of a in MKS/SI units= % 1f pa m^6',a1)\n",
+"printf(' \nvalue of b in MKS/SI units= % 1f ',b)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.9: chapter_7_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"a=1.64*10^-2//pa m^6 /mole^2\n",
+"b=2.17*10^-5//m^3/mole\n",
+"t=300//k\n",
+"v=10^-3//m^3/mole\n",
+"R=8.31//j/mole/k\n",
+"tc=33.2\n",
+"pc=1.295*10^6\n",
+"vc=6.5*10^-5\n",
+"//CALCULATIONS\n",
+"p=(((R*t)/(v-b))-(a/(v*v)))\n",
+"p1=(R*t)/v\n",
+"r=(8*pc*vc)/(3*tc)\n",
+"p2=(((r*t)/(v-b))-(a/(v*v)))\n",
+"p3=(r*t)/v\n",
+"//results\n",
+"printf(' value of pressure at 300k= % 1f pa',p)\n",
+"printf(' \n pressure using ideal gas condition= % 1f pa',p1)\n",
+"printf(' \nvalue of R at critical point= % 1f J/mole/k',r)\n",
+"printf(' \n using r value in vanderwaals equation p = % 1f pa',p2)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/8-thermodynamics.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/8-thermodynamics.ipynb
new file mode 100644
index 0000000..24d965b
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/8-thermodynamics.ipynb
@@ -0,0 +1,899 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 8: thermodynamics"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.10: chapter_8_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T1=20+273//k\n",
+"T2=273//k\n",
+"m=2//kg\n",
+"L=80000//cal/kg\n",
+"//CALCULATIONS\n",
+"Q2=m*L/3600\n",
+"w=(T1-T2)*Q2*4.2/(T2)\n",
+"//results\n",
+"printf(' \n minimum power output of the motor= % 1f H.P',w/746)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.11: chapter_8_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T1=20+273//k\n",
+"T2=273//k\n",
+"m=2//kg\n",
+"L=80000//cal/kg\n",
+"//CALCULATIONS\n",
+"Q2=m*L/3600\n",
+"w=(T1-T2)*Q2*4.2/(T2)\n",
+"//results\n",
+"printf(' \n minimum power output of the motor= % 1f H.P',w/746)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.12: chapter_8_example_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"p=10^5//N/m^2\n",
+"l=1//m\n",
+"a=0.2//m^2\n",
+"n=5\n",
+"//CALCULATIONS\n",
+"power=2*p*l*a*n/746\n",
+"//results\n",
+"printf(' \n horse power of engine= % 1f H P',power)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.13: chapter_8_example_13.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"dp=1//atm\n",
+"L=80000//cal\n",
+"T=273//k\n",
+"r=11/10\n",
+"//CALCULATIONS\n",
+"dv=(1-r)/1000\n",
+"dt=T*dv*(13600*9.81*0.76)/(L*4.2)\n",
+"//results\n",
+"printf(' \n depression in melting point of ice= % 1f c',-dt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.14: chapter_8_example_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"dt=0.5//c\n",
+"L=80000*4.2//J/kg\n",
+"T=273//k\n",
+"dv=0.000091//m^3\n",
+"//CALCULATIONS\n",
+"dp=(L*dt)/(T*dv*100000)\n",
+"//results\n",
+"printf(' \n pressure= % 1f atm',dp)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.15: chapter_8_example_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"dp=1.01*10^5//Nm^-2\n",
+"L=4563000*4.2//J\n",
+"dv=18.7*10^-3//m^3\n",
+"T=353//k\n",
+"//CALCULATIONS\n",
+"dT=(dp*T*dv)/L\n",
+"//results\n",
+"printf(' \n change in melting point= % 1f c',dT)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.16: chapter_8_example_16.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T=373//k\n",
+"L=537000*4.2//J\n",
+"dp=0.0212*13600*9.81\n",
+"dv=1.673//m^3\n",
+"//CALCULATIONS\n",
+"dT=dp*T*dv/L\n",
+"//results\n",
+"printf(' \n change in temperature of boiling water= % 1f c',dT)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.17: chapter_8_example_17.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variabes\n",
+"dp=(100-1)*1.01*10^5\n",
+"L=24500//J\n",
+"T=600//k\n",
+"d2=11010\n",
+"d1=10650\n",
+"//CALCULATIONS\n",
+"dv=(1/d2)-(1/d1)\n",
+"dT=dp*T*dv/L\n",
+"mp=T+(-dT)\n",
+"//results\n",
+"printf(' \n new melting point= % 1f c',mp)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.18: chapter_8_example_18.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"p=1.5//kg/cm2\n",
+"T=373//k\n",
+"v=1600//cc\n",
+"L=2240000//J/kg\n",
+"//CALCULATIONS\n",
+"dp=((p*1000*980)-(1.01*10^6))/10\n",
+"dv=(v-1)/1000\n",
+"dT=dp*T*dv/L\n",
+"T1=dT+T-273\n",
+"//results\n",
+"printf(' \n new temperature of cooker= % 1f c',T1)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.19: chapter_8_example_19.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"c1=1000\n",
+"T=373//k\n",
+"L=539300//cal\n",
+"r=604// cal/kg/deg\n",
+"//CALCULATIONS\n",
+"c2=c1-(r)-(L/T)\n",
+"//results\n",
+"printf(' \n specific heat of saturated steam= % 1f cal/kg',c2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.1: chapter_8_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"Q=50//cal\n",
+"W=20//cal\n",
+"Qi=36//cal\n",
+"Wi=-13//cal\n",
+"ui=10//cal\n",
+"ub=22//cal\n",
+"//CALCULATIONS\n",
+"du=Q-W\n",
+"Wibf=Qi-du\n",
+"Qfi=du+Wi\n",
+"Uf=du+ui\n",
+"Qbf=Uf-ub\n",
+"//results\n",
+"printf(' \n Wibf= % 1f cal',Wibf)\n",
+"printf(' \n Qfi= % 1f cal',Qfi)\n",
+"printf(' \n Uf= % 1f cal',Uf)\n",
+"printf(' \n Qbf= % 1f cal',Qbf)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.20: chapter_8_example_20.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m=0.1//kg\n",
+"v=1.01*10^-4//m^3\n",
+"vs=0.167404//m^3\n",
+"t1=101//c\n",
+"t2=99//c\n",
+"p1=0.788//m\n",
+"p2=0.7337//m\n",
+"T=373//k\n",
+"//CALCULATIONS\n",
+"v1=v/m\n",
+"v2=vs/m\n",
+"dv=v2-v1\n",
+"dt=t1-t2\n",
+"dp=p1-p2\n",
+"dP=dp*13600*9.81\n",
+"L=dP*T*dv/(dt*4.2)\n",
+"//results\n",
+"printf(' \n latent heat of steam= % 1f cal/kg',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.21: chapter_8_example_21.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T1=1100//k\n",
+"T3=200//k\n",
+"r=0.5\n",
+"//CALCULATIONS\n",
+"T=(T1-(T3*r))/(1+r)\n",
+"//results\n",
+"printf(' \n value of T= % 1f k',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.22: chapter_8_example_22.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T2=500//k\n",
+"T1=1000//k\n",
+"//CALCULATIONS\n",
+"r=1-(T2/T1)\n",
+"x=T1/r\n",
+"//results\n",
+"printf(' \n value of x= % 1f k',x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.23: chapter_8_example_23.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T1=900//k\n",
+"T2=300//k\n",
+"Q1=10^6//cal\n",
+"//CALCULATIONS\n",
+"r=(1-(T2/T1))\n",
+"r1=r*100\n",
+"w=r*Q1\n",
+"w1=w*4.2//J\n",
+"w2=w1/(3.6*10^6)\n",
+"w3=w1/(1.609*10^-19)\n",
+"//results\n",
+"printf(' \n efficiency= % 1f ',r1)\n",
+"printf(' \n work in KWH= % 1f KWH',w2)\n",
+"printf(' \n work in ev= % 1e ev',w3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.24: chapter_8_example_24.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T2=300///k\n",
+"T1=900//k\n",
+"T3=600//k\n",
+"Q2=15000//k.cal\n",
+"Q1=12000//k.cal\n",
+"//CALCULATIONS\n",
+"na=1-(T2/T1)\n",
+"nb=1-(T2/T3)\n",
+"w1=Q1*na\n",
+"w2=Q2*nb\n",
+"//results\n",
+"printf(' \n w1= % 1f kcal',w1)\n",
+"printf(' \n w2= % 1f kcal',w2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.25: chapter_8_example_25.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variab;es\n",
+"l=420//m\n",
+"g=9.81//m/sec^2\n",
+"c=1000\n",
+"//CALCULATIONS\n",
+"dt=(g*l)/(c*4.2)\n",
+"//results\n",
+"printf(' \n difference in temperature= % 1f c',dt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.26: chapter_8_example_26.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m=0.005//kg\n",
+"c=0.17//kcal/kg/c\n",
+"t1=12.4//c\n",
+"t2=10.2//c\n",
+"//CALCULATIONS\n",
+"du=m*c*(t1-t2)*4.2*1000\n",
+"//results\n",
+"printf(' \n change in internal energy= % 1f J',du)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.27: chapter_8_example_27.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"dq=-80\n",
+"dv=0.091*10^-6//m^3\n",
+"p=1.013*10^5//n/m^2\n",
+"//CALCULATIONS\n",
+"du=dq-(p*dv/46)\n",
+"//results\n",
+"printf(' \n change in internal energy= % 1f cal',du)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.28: chapter_8_example_28.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"p=1*10^5//n/m^2\n",
+"v2=2.6//litre\n",
+"v1=2.2//litre\n",
+"dq=250//j\n",
+"//CALCULATIONS\n",
+"dv=(v2-v1)*10^-3\n",
+"dw=p*dv\n",
+"du=dq-dw\n",
+"//results\n",
+"printf(' \n change in internal energy= % 1f J',du)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.29: chapter_8_example_29.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"v2=6//lit\n",
+"v1=2//lit\n",
+"r=3/2\n",
+"p1=1.01*10^5//n/m^2\n",
+"//CALCULATIONS\n",
+"g=(r+1)/r\n",
+"p2=p1*(v2/v1)^g\n",
+"w=(1/(g-1))*((p1*v2*10^-3)-(p2*v1*10^-3))\n",
+"//results\n",
+"printf(' \n work done= % 1f J',w)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.2: chapter_8_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"g=1.4\n",
+"T1=15+273//k\n",
+"r=2\n",
+"p=2//atm\n",
+"r1=0.5\n",
+"//CALCULATIONS\n",
+"T2=T1*r^(g-1)\n",
+"t2=T1*r1^((g-1)/g)\n",
+"//results\n",
+"printf(' \n final temperature= % 1f k',T2)\n",
+"printf(' \n temperature= % 1f k',t2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.3: chapter_8_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"r=1/20\n",
+"p1=1//atm\n",
+"g=1.4\n",
+"T1=273//k\n",
+"//CALCULATIONS\n",
+"p2=p1/r\n",
+"pad=p2^g\n",
+"T2=T1*((1/r)^(g-1))\n",
+"dt=T2-T1\n",
+"//RESULTS\n",
+"printf(' \n pressure required= % 1f atm',p2)\n",
+"printf(' \n pressure for adiabatic conditions= % 1f atm',pad)\n",
+"printf(' \n rise in temperature= % 1f c',dt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.4: chapter_8_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"R=8400//j/mole\n",
+"T1=273//k\n",
+"g=1.66\n",
+"r=2\n",
+"//CALCULATIONS\n",
+"T2=T1*r^(g-1)\n",
+"w=(R*(T1-T2))/(22400*(g-1))\n",
+"wi=R*T1*log(1/r)/22400\n",
+"//results\n",
+"printf(' \n amount of work done= % 1f J',w)\n",
+"printf(' \n isothermal work done= % 1f J',wi)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.5: chapter_8_example_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"r1=2\n",
+"r=2\n",
+"rv=0.75\n",
+"//CALCULATIONS\n",
+"g=log(r1/rv)/log(r)\n",
+"//results\n",
+"printf(' \n gamma value= % 1f ',g)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.6: chapter_8_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"t0=273//k\n",
+"d0=1.29//kg/m^3\n",
+"p=0.75//m\n",
+"t=273+17//k\n",
+"p0=0.76//m\n",
+"v=342.15//m/sec\n",
+"//CALCULATIONS\n",
+"d=t0*d0*p/(t*p0)\n",
+"g=(v*v*d)/(p*13600*9.81)\n",
+"//results\n",
+"printf(' \n gamma value= % 1f ',g)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.7: chapter_8_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"n=0.5\n",
+"n1=0.6\n",
+"T2=27+273//k\n",
+"//CALCULATIONS\n",
+"T1=T2/(1-n)\n",
+"T=T2/(1-n1)\n",
+"dt=T-T1\n",
+"//results\n",
+"printf(' \n source tempperature must be raised by= % 1f c',dt)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.8: chapter_8_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"w=100//watt\n",
+"T2=100+273//k\n",
+"T1=273//k\n",
+"L=80000//cal/kg\n",
+"//CALCULATIONS\n",
+"dt=T2-T1\n",
+"Q1=T2*w/dt\n",
+"m=(Q1-w)*60/(4.2*L)\n",
+"//results\n",
+"printf(' \n mass of ice melts in 1 min= % 1f kg',m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.9: chapter_8_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"L=80000//cal/kg\n",
+"T1=27+273//k\n",
+"T2=0+273//k\n",
+"//CALCULATIONS\n",
+"Q1=T1*L/T2\n",
+"w=4.2*(Q1-L)\n",
+"c=L/(Q1-L)\n",
+"//results\n",
+"printf(' \n coefficient of performance= % 1f ',c)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Heat_And_Thermodynamics_by_D_S_Mathur/9-entropy.ipynb b/Heat_And_Thermodynamics_by_D_S_Mathur/9-entropy.ipynb
new file mode 100644
index 0000000..1017bdd
--- /dev/null
+++ b/Heat_And_Thermodynamics_by_D_S_Mathur/9-entropy.ipynb
@@ -0,0 +1,512 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 9: entropy"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.10: chapter_9_example_10.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"st=1.75\n",
+"sw=0.30\n",
+"t=100//c\n",
+"T=273+t//k\n",
+"//CALCULATIONS\n",
+"L=T*(st-sw)\n",
+"//results\n",
+"printf(' \n specific latent heat of steam= % 1f cal/gm',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.11: chapter_9_example_11.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"r=3\n",
+"n=2\n",
+"R=8314\n",
+"//CALCULATIONS\n",
+"ds=2.3026*n*R*log(r)\n",
+"//results\n",
+"printf(' \n change in entropy= % 1f j/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.13: chapter_9_example_13.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m1=90//gm\n",
+"m2=10//gm\n",
+"T1=373//k\n",
+"T2=273//k\n",
+"T3=331.2//k\n",
+"l=540\n",
+"//CALCULATIONS\n",
+"ds=(m1+m2)*log(T3/T2)-m2*l/T1+m2*log(T3/T1)\n",
+"//results\n",
+"printf(' change in entropy = % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.14: chapter_9_example_14.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m1=3//gm\n",
+"m2=28\n",
+"ds=0.621//J/k\n",
+"//CALCULATIONS\n",
+"r=ds*m2/(m1*8.31)\n",
+"a=2.3026^r\n",
+"//results\n",
+"printf(' change in volume = % 1f ',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.15: chapter_9_example_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"e=0.31\n",
+"e1=1.76//cal/gm/k\n",
+"t=100//c\n",
+"T=273+t//k\n",
+"//-CALCULATIONS\n",
+"ds=e1-e\n",
+"dq=ds*T\n",
+"//results\n",
+"printf(' \n heat of vaporisation at this temperature= % 1f cal/gm',dq)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.16: chapter_9_example_16.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"i=3//amp\n",
+"r=10//ohm\n",
+"t=27//c\n",
+"T=273+t//k\n",
+"//CALCULATIONS\n",
+"dq1=0\n",
+"ds1=dq1/T\n",
+"dq2=i*i*r\n",
+"ds2=dq2/T\n",
+"//results\n",
+"printf(' \n change in entropy of resistor= % 1f j/k',ds1)\n",
+"printf(' \n change in entropy of universe= % 1f j/k',ds2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.17: chapter_9_example_17.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m1=1//gm\n",
+"m2=28\n",
+"cv=0.18\n",
+"T2=373//k\n",
+"T1=323//k\n",
+"//CALCULATIONS\n",
+"ds=m1*cv*log(T2/T1)/m2\n",
+"//results\n",
+"printf(' change in entropy = % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.18: chapter_9_example_18.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"T1=40//k\n",
+"T2=120//k\n",
+"c1=0.076\n",
+"c2=0.00026\n",
+"c3=0.15\n",
+"//CALCULATIONS\n",
+"r1=c1*(T2-T1)\n",
+"r2=(c2/2)*(T2^2-T1^2)\n",
+"r3=c3*log(T2/T1)\n",
+"ds=5*(r1-r2-r3)\n",
+"//results\n",
+"printf(' change in entropy = % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.1: chapter_9_example_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation\n",
+"m=10//gm\n",
+"l=80//\n",
+"t=273//k\n",
+"//CALCULATIONS\n",
+"dq=m*l\n",
+"ds=dq/t\n",
+"//results\n",
+"printf(' \n change in entropy= % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.2: chapter_9_example_2.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m=0.001//kg\n",
+"l=80000//cal/kg\n",
+"T1=273//k\n",
+"T2=373//k\n",
+"s=1000\n",
+"l1=540000//cal/kg\n",
+"//CALCULATIONS\n",
+"ds=(m*l/T1)+(m*s*log(T2/T1))+(m*l1/T2)\n",
+"//results\n",
+"printf(' change in entropy = % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.3: chapter_9_example_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m=0.001//kg\n",
+"s=500//cal/kg\n",
+"li=80000//cal/kg\n",
+"l1=540000//cal/kg\n",
+"T1=273//k\n",
+"T2=263//k\n",
+"T3=373//k\n",
+"s1=1000//cal/kg\n",
+"//CALCULATIONS\n",
+"d1=m*s*log(T1/T2)\n",
+"d2=m*li/T1\n",
+"d3=m*s1*log(T3/T1)\n",
+"d4=m*l1/T3\n",
+"d5=d4+d3+d2+d1\n",
+"//results\n",
+"printf(' increase in entropy = % 1f cal/k',d5)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.4: chapter_9_example_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m1=0.08//kg\n",
+"m2=0.12//kg\n",
+"t1=20//c\n",
+"t2=50//c\n",
+"T1=t1+273//k\n",
+"T2=t2+373//k\n",
+"s=1000//cal/kg\n",
+"//CALCULATIONS\n",
+"t=(m2*t2+m1*t1)/(m1+m2)\n",
+"T3=t+273\n",
+"s1=m1*s*log(T3/T1)\n",
+"s2=m2*s*log(T3/T2)\n",
+"ds=s1+s2\n",
+"//results\n",
+"printf(' change in entropy of universe = % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.6: chapter_9_example_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"r=4\n",
+"//CALCULATIONS\n",
+"w=log(r)\n",
+"//results\n",
+"printf(' change in entropy = % 1f R/J cal for each',w)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.7: chapter_9_example_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m=1//kg\n",
+"c=1000\n",
+"T1=273//k\n",
+"T2=50+273//k\n",
+"l=571700//cal/kg\n",
+"//CALCULATIONS\n",
+"ds=m*c*log(T2/T1)+m*l/T2\n",
+"//results\n",
+"printf(' difference in entropy = % 1f cal per degree c',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.8: chapter_9_example_8.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"m=0.01//kg\n",
+"T1=800//k\n",
+"T2=500//k\n",
+"T3=400//k\n",
+"s1=60//cal/kg/k\n",
+"s2=70//cal/kg/k\n",
+"l=14000//cal/kg\n",
+"//CALCULATIONS\n",
+"ds=m*s1*log(T2/T3)+m*l/T2+m*s2*log(T1/T2)\n",
+"//results\n",
+"printf(' change in entropy = % 1f cal/k',ds)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.9: chapter_9_example_9.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc\n",
+"//initialisation of variables\n",
+"c1=0.08\n",
+"c2=0.003\n",
+"c3=0.1\n",
+"T2=100//k\n",
+"T1=50//k\n",
+"//CALCULATIONS\n",
+"r1=c1*(T2-T1)\n",
+"r2=(c2/2)*(T2^2-T1^2)\n",
+"r3=c3*log(T2/T1)\n",
+"ds=5*(r1-r2-r3)\n",
+"//results\n",
+"printf(' change in entropy = % 1f cal/k',ds)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}