initial commit / add all books

23 files changed, 502 insertions, 0 deletions

diff --git a/2192/CH4/EX4.1/4_1.sce b/2192/CH4/EX4.1/4_1.sce
new file mode 100755
index 000000000..ab70ed9c0
--- /dev/null
+++ b/2192/CH4/EX4.1/4_1.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 4.1\n\n')

+

+P=1000 //power absorbed in watts

+k_0=8.854*10^-12 //permittivity of free space

+k=3.6 //relative permittivity of wood

+A=0.5 //area of cross section of plate in m^2

+t=0.025 //thickness in m

+f=25*10^6 //frequency in hertz

+

+C=k_0*k*A/t //capacitance of capacitor formed

+phi=acos(0.046) //power factor angle

+delta=%pi/2 - phi 

+

+V = sqrt(P/(2*%pi*f*C*delta))

+printf('Voltage employed is %.2f volts',V)

diff --git a/2192/CH4/EX4.10/4_10.sce b/2192/CH4/EX4.10/4_10.sce
new file mode 100755
index 000000000..b9265d5b0
--- /dev/null
+++ b/2192/CH4/EX4.10/4_10.sce
@@ -0,0 +1,20 @@
+clc,clear

+printf('Example 4.10\n\n')

+

+P=20*1000 //power supplied in watts

+V=220 //supply voltage

+e=0.9;k=0.6; //emissivity and radiant efficiency

+rho=100*10^-6//specific resistance

+

+l_by_d2 = %pi*V^2/(4*rho*P) //ratio of l and d^2                              (i)

+T1=1170+273; T2=500+273; //temperatures of wire and charge

+H=5.72*k*e*(T1^4-T2^4)/1000^4 //heat dissipated from surface

+

+//Surface area = %pi*d*l

+//total heat dissipated = electric power input and squaring the equation

+d2l2= ( P/(H*%pi) )^2 //    d^2  * l^2                                        (ii)

+//using expression (i) and expression (ii)

+l =(d2l2*l_by_d2)^(1/3)

+printf('Length of wire = %.1f metres',l/100)

+d=sqrt( l/l_by_d2 ) 

+printf('\nSize of wire = %.1f cm',d)

diff --git a/2192/CH4/EX4.11/4_11.sce b/2192/CH4/EX4.11/4_11.sce
new file mode 100755
index 000000000..660dfcef1
--- /dev/null
+++ b/2192/CH4/EX4.11/4_11.sce
@@ -0,0 +1,17 @@
+clc,clear

+printf('Example 4.11\n\n')

+

+mass=500 //quantity of brass to be melted

+T1=920;T2=20; //final and initial temperature

+S=0.094 //specific heat of brass

+H1=mass*S*(T1-T2) //heat to raise temperature

+

+L=39 //latent heat of fusion of brass

+H2=mass*L//heat reqd to heat metal at 920

+

+H=H1+H2 //total heat required

+efficiency=60.2/100 //furnace efficiency 

+Energy_required = H *4180/(3600*1000*efficiency) //constants used for unit conversion

+printf('Energy required = %.1f kWh\n',Energy_required)

+time=1/2 //time for melting in hours

+printf('Average power input= %.1f kW',Energy_required/time)

diff --git a/2192/CH4/EX4.12/4_12.sce b/2192/CH4/EX4.12/4_12.sce
new file mode 100755
index 000000000..796c3e4a4
--- /dev/null
+++ b/2192/CH4/EX4.12/4_12.sce
@@ -0,0 +1,13 @@
+clc,clear

+printf('Example 4.12\n\n')

+

+V=250;R=190

+//part(i)

+R1=1/(R^-1+R^-1) //equivalent resistance in parallel

+P1=V^2/R1 //power drawn in parallel

+printf('(i)Power drawn in parallel = %.2f watts',P1)

+

+//part(ii)

+R2=R+R //equivalent resistance in series

+P2=V^2/R2 //power drawn in series

+printf('\n(ii)Power drawn in series= %.2f watts',P2)

diff --git a/2192/CH4/EX4.13/4_13.sce b/2192/CH4/EX4.13/4_13.sce
new file mode 100755
index 000000000..1234b51ff
--- /dev/null
+++ b/2192/CH4/EX4.13/4_13.sce
@@ -0,0 +1,42 @@
+clc,clear

+printf('Example 4.13\n\n')

+

+//PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) 

+V=230;R=100;

+P_each = V^2/R

+

+//part(a)

+P1a=6*P_each  //power consumed

+//part(b)

+P1b=V^2/(R+R+R) + V^2/(R+R+R)  //power consumed

+

+//PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) 

+V=400/sqrt(3)

+

+//part(a)

+R_eq=R/2 //equivalent resistance of given configuration

+P2a=V^2/R_eq //power consumed

+//part(b)

+R_eq=R+R //equivalent resistance of given configuration

+P2b=V^2/R_eq //power consumed

+

+//PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) 

+V=400

+R_eq=R/2 //equivalent resistance of given configuration

+//part(a)

+P3a=V^2/R_eq //power consumed

+//part(b)

+R_eq=R+R //equivalent resistance of given configuration

+P3b=V^2/R_eq //power consumed

+

+printf('Part(i)\n')

+printf('(a)Power consumed = %.3f kW\n',P1a/1000)

+printf('(b)Power consumed = %.0f watts\n',P1b)

+printf('Part(ii)\n')

+printf('(a)Power consumed = %.3f kW\n',P2a/1000)

+printf('(b)Power consumed = %.3f kW\n',P2b/1000)

+printf('Part(iii)\n')

+printf('(a)Power consumed = %.1f kW\n',P3a/1000)

+printf('(b)Power consumed = %.0f watts\n',P3b)

+

+printf('\nAnswers may mismatch due to calculation error in book')

diff --git a/2192/CH4/EX4.14/4_14.sce b/2192/CH4/EX4.14/4_14.sce
new file mode 100755
index 000000000..fed2e0373
--- /dev/null
+++ b/2192/CH4/EX4.14/4_14.sce
@@ -0,0 +1,21 @@
+clc,clear

+printf('Example 4.14\n\n')

+

+P=15*1000 //power supplied

+V=220 //supply voltage

+k=0.6;e=0.9; //radiating efficiency and emissivity

+rho = 1.016*10^-6 //specific resistance

+

+l_by_d2 = %pi*V^2/(4*rho*P) //ratio of l and d^2                              (i)

+

+T1=1000+273; T2=600+273; //temperatures of wire and charge

+H=5.72*k*e*(T1^4-T2^4)/100^4 //heat dissipated from surface

+

+//since heat dissipated = electrical power input;

+dl2=(   P/(H*%pi)   )^2//product of d and l                                   (ii)

+

+//multiplying expression(i) and expression (ii)

+l=(l_by_d2*dl2)^(1/3) //length of wire

+printf('Length of wire = %.2f m\n',l)

+d= sqrt(dl2)/l //diameter of wire

+printf('Diameter of wire = %.2f mm',1000*d)

diff --git a/2192/CH4/EX4.15/4_15.sce b/2192/CH4/EX4.15/4_15.sce
new file mode 100755
index 000000000..b8f4d29a2
--- /dev/null
+++ b/2192/CH4/EX4.15/4_15.sce
@@ -0,0 +1,22 @@
+clc,clear

+printf('Example 4.15\n\n')

+

+P=30*1000/3 //power per phase

+V_ph=400/sqrt(3) //phase voltage

+R=(V_ph)^2/P //resistance of strip

+t=0.025*10^-2 //thickness of strip

+S=1.03*10^-6 //specific resistance of nichrome alloy

+l_by_w = R*t/S //because R=specific_resistance*l/(w*t)                                          (i)

+

+k=0.6;e=0.9; //radiating efficiency and emissivity

+T1=1100+273; T2=700+273; //temperatures of wire and charge

+H=5.72*k*e*(T1^4-T2^4)/100^4 //heat dissipated from surface

+

+//surface_area = 2*w*l 

+//Since, heat dissipated = Power input ; surface_area = P/H

+surface_area = P / H

+wl=surface_area /2 //product of w and l                                       (ii)

+

+//dividing expression(ii) by expression(i)

+w=sqrt(wl/l_by_w)

+printf('Width of strip = %.2f mm',w*1000)

diff --git a/2192/CH4/EX4.16/4_16.sce b/2192/CH4/EX4.16/4_16.sce
new file mode 100755
index 000000000..d06ed5ce5
--- /dev/null
+++ b/2192/CH4/EX4.16/4_16.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 4.16\n\n')

+

+P=1000 //power absorbed in watts

+k_0=8.854*10^-12 //permittivity of free space

+k=3.6 //relative permittivity of wood

+A=0.5 //area of cross section of plate in m^2

+t=0.025 //thickness in m

+f=25*10^6 //frequency in hertz

+

+C=k_0*k*A/t //capacitance of capacitor formed

+phi=acos(0.046) //power factor angle

+delta=%pi/2 - phi 

+

+V = sqrt(P/(2*%pi*f*C*delta))

+printf('Voltage employed is %.2f volts',V)

diff --git a/2192/CH4/EX4.17/4_17.sce b/2192/CH4/EX4.17/4_17.sce
new file mode 100755
index 000000000..6a442b438
--- /dev/null
+++ b/2192/CH4/EX4.17/4_17.sce
@@ -0,0 +1,33 @@
+clc,clear
+printf('Example 4.17\n\n')
+
+m=10*1000 //10 tonnes of steel
+S=444//specific heat of steel
+L=37.25*1000 //latent heat of fusion of steel
+T2=1370;T1=20//final and initial temperatures
+
+Energy=(m*S*(T2-T1) + m*L)  / 3600 //energy required to melt 10 tonne steel in Wh
+efficiency= 50/100
+time_taken = 2 //time taken in melting of heat in hours
+average_output = Energy/time_taken
+average_input= average_output/ efficiency
+printf('Average input to furnace = %.1f kW\n',average_input/1000)
+
+current_input=9000
+resistance= 0.003 //resistance of furnace leads including transformer
+reactance= 0.005  //reactance of furnace leads including transformer
+V1= current_input*resistance //voltage drop due to resistance
+V2= current_input*reactance //voltage drop due to reactance
+
+//Solving for V_A (arc voltage)
+//V_opencircuit= sqrt((V_A=V1)^2+ V2^2)
+//cos_phi=  V_A+27 / sqrt((V_A-V1)^2+ V2^2)
+//Input power = 3*current_input* V_opencircuit *cos_phi
+
+V_A= average_input/ (3*current_input)   -27
+printf('Arc voltage = %.1f V\n',V_A)
+V_opencircuit= sqrt((V_A-V1)^2+ V2^2)
+total_VA=3*current_input* V_opencircuit
+printf('Total kVA taken from supply = %.0f kVA',total_VA/1000)
+
+printf('\n\nAnswers mimatch because 27 volts was left unconsidered in last 2 steps')
diff --git a/2192/CH4/EX4.18/4_18.sce b/2192/CH4/EX4.18/4_18.sce
new file mode 100755
index 000000000..cf449e3a0
--- /dev/null
+++ b/2192/CH4/EX4.18/4_18.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 4.18\n\n')

+

+m=1.8 //mass of aluminium to be melt

+t1=15 //initial temperature

+t2=660 //melting temperature

+

+S=880 //specific heat of aluminium

+L=32000 //latent heat of aluminium

+

+heat_required= m*S*(t2-t1) + m*L

+heat_required= heat_required*2.78*10^-7 //converting Joules to kWh

+T=10//time taken for melting in minutes

+energy_input=5*(T/60) //In kWh

+efficiency_of_furnace = 100* heat_required / energy_input

+printf('Efficiency of furnace = %.0f percent',efficiency_of_furnace )

diff --git a/2192/CH4/EX4.19/4_19.sce b/2192/CH4/EX4.19/4_19.sce
new file mode 100755
index 000000000..a4999ad10
--- /dev/null
+++ b/2192/CH4/EX4.19/4_19.sce
@@ -0,0 +1,30 @@
+clc,clear

+printf('Example 4.19\n\n')

+

+arc_voltage=50

+I=5000 //current drawn

+resistance= 0.002 //resistance of furnace leads including transformer

+reactance= 0.004  //reactance of furnace leads including transformer

+V1= I*resistance //voltage drop due to resistance of transformer

+V2= I*reactance //voltage drop due to reactance of transformer

+V_OC= sqrt(  (arc_voltage+V1)^2 + V2^2 ) //open circuit phase voltage of transformer secondary

+

+//part(i)

+pf=(arc_voltage+V1)/V_OC

+power_drawn= I*V_OC*pf //power drawn from supply per phase

+total_power_drawn =power_drawn*3

+printf('Power factor of supply = %.4f\n',pf)

+printf('kW drawn from supply= %.0f kW\n',total_power_drawn/1000)

+

+//part(ii)

+m=2*10^3 //mass of steel to melt

+S=120//specific heat of steel

+L=8890//latent heating of fusion

+T2=1370;T1=20; //melting point and initial temperature

+efficiency=65/100//efficiency of furnace

+energy_required= ( m*S*(T2-T1) + m*L)   /869 //energy reqd to melt steel in watts

+power_utilised= total_power_drawn * efficiency

+time= energy_required /power_utilised  //time required for melting

+printf('Time required for melting = %d minutes %d seconds\n\n',60*time,60*(60*time- floor(60*time) ))

+

+printf('Answers might slightly vary due to lack of accuracy in energy required calculation')

diff --git a/2192/CH4/EX4.2/4_2.sce b/2192/CH4/EX4.2/4_2.sce
new file mode 100755
index 000000000..57aa9be25
--- /dev/null
+++ b/2192/CH4/EX4.2/4_2.sce
@@ -0,0 +1,21 @@
+clc,clear

+printf('Example 4.2\n\n')

+

+P=16*1000 //power supplied in watts

+V=220 //supply voltage

+e=0.9;k=0.57; //emissivity and radiant efficiency

+rho=1.09*10^-12//resistivity in ohm-metre

+

+l_by_d2 = %pi*V^2/(4*rho*P) //ratio of l and d^2                              (i)

+T1=1170+273; T2=500+273; //temperatures of wire and charge

+H=5.72*k*e*(T1^4-T2^4)/100^4 //heat dissipated from surface

+

+//Surface area = %pi*d*l

+//total heat dissipated = electric power input and squaring the equation

+d2l2= ( P/(H*%pi) )^2 //d^2*l^2                                              (ii)

+//multiplying expression (i) and expression (ii)

+l =(1/100)*(d2l2*l_by_d2)^(1/3)

+printf('Length of wire = %.0f metre',l)

+d=1000*sqrt(d2l2)/l

+//d=sqrt( l/l_by_d2 ) 

+printf('\nDiameter of wire = %.2f mm',d)

diff --git a/2192/CH4/EX4.20/4_20.sce b/2192/CH4/EX4.20/4_20.sce
new file mode 100755
index 000000000..7a422f62b
--- /dev/null
+++ b/2192/CH4/EX4.20/4_20.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 4.20\n\n')

+

+V=10 //secondary voltage

+P=400*10^3 //power drawn in watts

+phi=acos(0.6) //power factor angle

+I= P/(V*cos(phi)) //secondary current

+Z=V/I //impedance of secondary circuit 

+R=Z*cos(phi) //resistance of secondary circuit when hearth is full

+X=Z*sin(phi) //reactance of secondary circuit

+

+//x is ratio of height of charge to full hearth

+//Heat produced will be maximum when resistance of secondary circuit equals reactance ; i.e. when R/x= X

+

+x=R/X

+printf('Height of charge should be %.2f times height of hearth to obtain maximum heat',x)

diff --git a/2192/CH4/EX4.21/4_21.sce b/2192/CH4/EX4.21/4_21.sce
new file mode 100755
index 000000000..d56513246
--- /dev/null
+++ b/2192/CH4/EX4.21/4_21.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 4.21\n\n')

+

+V= 0.5*0.25*0.02//volume of plywood to be heated

+D=600 //density of plywood in kg/m^3

+W=V*D

+

+specific_heat = 1500

+T1=25;T2=125; //initial and final temperature

+heat= specific_heat * W * (T2-T1)/(60*60) //in W-Hr

+T=10 //duration of heating in minutes

+power_required = heat/(T/60)

+efficiency= 50/100 //efficiency of process

+power_input= power_required/ efficiency

+

+printf('Power required for heating = %.0f watts',power_input)

diff --git a/2192/CH4/EX4.22/4_22.sce b/2192/CH4/EX4.22/4_22.sce
new file mode 100755
index 000000000..353b3166c
--- /dev/null
+++ b/2192/CH4/EX4.22/4_22.sce
@@ -0,0 +1,18 @@
+clc,clear

+printf('Example 4.22\n\n')

+

+P=200//power absorbed in watts

+phi=acos(0.05) //power factor angle

+f=3*10^6 //supply frequency in hertz

+k_0=8.854*10^-12 //permittivity of free space

+k=5 //relative permittivity of material

+A=1500*10^-6 //Area of slab

+t=20*10^-3  //thickness of insulating material

+

+C=k_0*k*A/t //capacitance of capacitor formed

+V=sqrt(P/(2*%pi*f*C*cos(phi))) //voltage required

+printf('Voltage required for heating = %.0f V',V)

+I=P/(V*cos(phi)) //current flowing through material

+printf('\nCurrent flowing through material = %.1f A',I)

+

+printf('\n\nWARNING :Answers may not match due to rounding off')

diff --git a/2192/CH4/EX4.23/4_23.sce b/2192/CH4/EX4.23/4_23.sce
new file mode 100755
index 000000000..254b07bc6
--- /dev/null
+++ b/2192/CH4/EX4.23/4_23.sce
@@ -0,0 +1,25 @@
+clc,clear

+printf('Example 4.23\n\n')

+

+A1= (25-5)*2*10^-4 //area of air envelope

+A2=5*2*10^-4 //Area of plywood in m^2

+t=2/100 //distance between electrodes

+t1=1/100 //thickness of plywood in m

+t2=(2-1)/100 //thickness of air envelope

+eps_0 = 8.854*10^-12 //permittivity of free space

+eps_r1 =5 //relative permittivity of plywood

+eps_r2 =1 //relative permittivity of air

+

+//capacitance of capacitor

+C= eps_0 * (  (A1*eps_r2/t) +  (A2/((t1/eps_r1)+(t2/eps_r2)))  )

+

+P=1000 //power consumed

+f=10*10^6 //frequency of electric current

+phi=acos(0.04) //power factor angle

+

+//part(i)

+V = sqrt(P/(2*%pi*f*C*cos(phi)))  //voltage across the electrode

+printf('(i)Voltage across the electrode = %.0f V',V)

+//part(ii)

+I=P/(V*cos(phi)) //current through plywood

+printf('\n(ii)Current through plywood = %.3f A',I)

diff --git a/2192/CH4/EX4.3/4_3.sce b/2192/CH4/EX4.3/4_3.sce
new file mode 100755
index 000000000..96761746a
--- /dev/null
+++ b/2192/CH4/EX4.3/4_3.sce
@@ -0,0 +1,22 @@
+clc,clear

+printf('Example 4.3\n\n')

+

+P=30*10^3/3 //power per phase

+V_ph=400/sqrt(3) //phase voltage

+R=(V_ph)^2/P

+

+//l and w are length and width respectively

+rho= 101.6*10^-8 //resistivity

+t=0.254*10^-3 //thickness of nickel-chrome strip

+l_by_w = R*t/rho //ratio of l and w                                           (i)

+

+k=0.5;e=0.9; //radiating efficiency and emissivity

+T1=1100+273; T2=700+273; //temperatures of wire and charge

+H=5.72*k*e*(T1^4-T2^4)/100^4 //heat dissipated from surface

+

+//surface are for heat dissipation = 2*w*l

+//heat dissipated = power input

+wl= P/(2*H) //                                                                (ii)

+//dividing expression (ii) by expression (i)

+w= sqrt(wl/l_by_w)

+printf('Width of strip = %.1f mm',w*1000)

diff --git a/2192/CH4/EX4.4/4_4.sce b/2192/CH4/EX4.4/4_4.sce
new file mode 100755
index 000000000..7612dd32c
--- /dev/null
+++ b/2192/CH4/EX4.4/4_4.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 4.4\n\n')

+

+surface_area= 6 //surface area of tank

+l=sqrt(surface_area/6) //length of one side of tank

+volume=l^3

+m=6*90/100  * 1000 //mass of water to be heated daily in kilogram

+S=4200//specific heat of water

+t2=65;t1=20;//final and initial temperature

+heat=m*S*(t2-t1)*10^-6 /3.6 // heat required for raising the temperature in kWh

+losses =6.3*surface_area*(t2-t1)*24/1000 //losses from surface of tank 24 hours in kWh 

+energy_supplied= heat+losses

+loading= energy_supplied/24 //in kW

+printf('Loading = %.1f kW\n',loading) 

+efficiecny=100*heat/energy_supplied

+printf('Efficiency of tank = %.1f percent',efficiecny)

diff --git a/2192/CH4/EX4.5/4_5.sce b/2192/CH4/EX4.5/4_5.sce
new file mode 100755
index 000000000..08c988f67
--- /dev/null
+++ b/2192/CH4/EX4.5/4_5.sce
@@ -0,0 +1,12 @@
+clc,clear

+printf('Example 4.5\n\n')

+

+m=2.5 //quantity of aluminium to be melted

+t1=15;t2=658;//melting point and initial temperature

+S=0.212 *1000*4.18 //specific bheat of aluminium

+L=320000//latent heat of aluminium

+W=(  m*S*(t2-t1) + m*L  ) *10^-6/ 3.6 // heat required for melting in kWh

+energy_input = 5*15/60 //converting to kWh

+efficiency = 100*W/energy_input //efficiency of furnace

+

+printf('Efficiency of furnace = %.1f percent',efficiency)

diff --git a/2192/CH4/EX4.6/4_6.sce b/2192/CH4/EX4.6/4_6.sce
new file mode 100755
index 000000000..7a7049aca
--- /dev/null
+++ b/2192/CH4/EX4.6/4_6.sce
@@ -0,0 +1,14 @@
+clc,clear

+printf('Example 4.6\n\n')

+

+P=400 //power absorbed in watts

+phi=acos(0.05) //power factor angle

+f=30*10^6 //frequency in hertz

+k_0=8.854*10^-12 //permittivity of free space

+k=5 //relative permittivity of wood

+A=150*10^-4 //area of cross section of plate in m^2

+t=0.01 //thickness in m

+

+C=k_0*k*A/t //capacitance of capacitor formed

+V = sqrt(P/(2*%pi*f*C*cos(phi)))

+printf('Necessary voltage is %.2f volts',V)

diff --git a/2192/CH4/EX4.7/4_7.sce b/2192/CH4/EX4.7/4_7.sce
new file mode 100755
index 000000000..b8ace9951
--- /dev/null
+++ b/2192/CH4/EX4.7/4_7.sce
@@ -0,0 +1,24 @@
+clc,clear

+printf('Example 4.7\n\n')

+

+P=400 //power absorbed in watts

+phi=acos(0.05) //power factor angle

+f=40*10^6 //frequency in hertz

+k_0=8.854*10^-12 //permittivity of free space

+k=5 //relative permittivity of wood

+A=200*10^-4 //area of cross section of plate in m^2

+t=0.02 //thickness in m

+

+C=k_0*k*A/t //capacitance of capacitor formed

+

+V = sqrt(P/(2*%pi*f*C*cos(phi)))

+printf('Necessary voltage is %.0f volts',V)

+

+I=P/(V*cos(phi))

+printf('\nCurrent flowing through material is %.3f Amp',I)

+

+//heat produced=f*V^2 ; 

+V_2=700 //new limited voltage

+f2 = f*(V/V_2)^2

+printf('\nRequired frequency is %.1f*10^6 Hz',f2/10^6)

+

diff --git a/2192/CH4/EX4.8/4_8.sce b/2192/CH4/EX4.8/4_8.sce
new file mode 100755
index 000000000..c8d7626e6
--- /dev/null
+++ b/2192/CH4/EX4.8/4_8.sce
@@ -0,0 +1,30 @@
+clc,clear

+printf('Example 4.8\n\n')

+

+arc_voltage=50

+I=5000 //current drawn

+resistance= 0.002 //resistance of furnace leads including transformer

+reactance= 0.004  //reactance of furnace leads including transformer

+V1= I*resistance //voltage drop due to resistance of transformer

+V2= I*reactance //voltage drop due to reactance of transformer

+V_OC= sqrt(  (arc_voltage+V1)^2 + V2^2 ) //open circuit phase voltage of transformer secondary

+

+//part(i)

+pf=(arc_voltage+V1)/V_OC

+power_drawn= I*V_OC*pf //power drawn from supply per phase

+total_power_drawn =power_drawn*3

+printf('Power factor of supply = %.4f\n',pf)

+printf('kW drawn from supply= %.0f kW\n',total_power_drawn/1000)

+

+//part(ii)

+m=2*10^3 //mass of steel to melt

+S=120//specific heat of steel

+L=8890//latent heating of fusion

+T2=1370;T1=20; //melting point and initial temperature

+efficiency=65/100//efficiency of furnace

+energy_required= ( m*S*(T2-T1) + m*L)   /869 //energy reqd to melt steel in watts

+power_utilised= total_power_drawn * efficiency

+time= energy_required /power_utilised  //time required for melting

+printf('Time required for melting = %d minutes %d seconds\n\n',60*time,60*(60*time- floor(60*time) ))

+

+printf('Answers might slightly vary due to lack of accuracy in energy required calculation')

diff --git a/2192/CH4/EX4.9/4_9.sce b/2192/CH4/EX4.9/4_9.sce
new file mode 100755
index 000000000..833539e2f
--- /dev/null
+++ b/2192/CH4/EX4.9/4_9.sce
@@ -0,0 +1,42 @@
+clc,clear

+printf('Example 4.9\n\n')

+

+//PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) PART(i) 

+V=230;R=100;

+P_each = V^2/R

+

+//part(a)

+P1a=6*P_each  //power consumed

+//part(b)

+P1b=V^2/(R+R+R) + V^2/(R+R+R)  //power consumed

+

+//PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) PART(ii) 

+V=400/sqrt(3)

+

+//part(a)

+R_eq=R/2 //equivalent resistance of given configuration

+P2a=V^2/R_eq //power consumed

+//part(b)

+R_eq=R+R //equivalent resistance of given configuration

+P2b=V^2/R_eq //power consumed

+

+//PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) PART(iii) 

+V=400

+R_eq=R/2 //equivalent resistance of given configuration

+//part(a)

+P3a=V^2/R_eq //power consumed

+//part(b)

+R_eq=R+R //equivalent resistance of given configuration

+P3b=V^2/R_eq //power consumed

+

+printf('Part(i)\n')

+printf('(a)Power consumed = %.3f kW\n',P1a/1000)

+printf('(b)Power consumed = %.0f watts\n',P1b)

+printf('Part(ii)\n')

+printf('(a)Power consumed = %.3f kW\n',P2a/1000)

+printf('(b)Power consumed = %.3f kW\n',P2b/1000)

+printf('Part(iii)\n')

+printf('(a)Power consumed = %.1f kW\n',P3a/1000)

+printf('(b)Power consumed = %.0f watts\n',P3b)

+

+printf('\nAnswers may mismatch due to calculation error in book')