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|
{
"metadata": {
"name": "",
"signature": "sha256:051dd4d8e63ef61b5430123d8cd0a562c5bdd2cd67fa5b75b947bfd8e0093f34"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter6:ELECTROMAGNETICS"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg1:pg-206"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"r=1 #radius in meter\n",
"H=2 #magnitude of field vector in amp/meter\n",
"pi=1 #let\n",
"I=H*2*pi*r \n",
"print\"Current in the wire is %d*pi amp\"%I"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Current in the wire is 4*pi amp\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg5:pg-212"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"sigma=1e-4 #conductivity in siemen/m\n",
"Er=2.25 #relative permittivity \n",
"E0=1/(4*math.pi*9e9) #permittivity of free space\n",
"#E=5e-6*sin(9e9*t) is the electric field in the material volt/m (given)\n",
"#J= sigma*E = 1e-4*5e-6*sin(9e9*t)= 5e-10sin(9e9*t)is Conduction current density in A/m**2 \n",
"#d(E)/dt= 5e-6*9e9*cos(9e9*t)\n",
"#Jd=E0*Er*(d(E)/dt) is Displacement current density in A/m**2\n",
"print\"Conduction current density is %s*sin(9e9*t) A/m**2\"%(sigma*5e-6)\n",
"print\"Displacement current density is %s*cos(9e9*t) A/m**2\"%round((E0*Er*5e-6*9e9),9)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Conduction current density is 5e-10*sin(9e9*t) A/m**2\n",
"Displacement current density is 8.95e-07*cos(9e9*t) A/m**2\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg13:pg-236"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"H0=1 #magnitude of field vector in amp/meter\n",
"mu_0=4*round(math.pi,2)*1e-7 #permeability of free space in H/m\n",
"e0=8.85e-12 #permittivity of free space in F/m\n",
"E0=H0*math.sqrt(mu_0/e0)\n",
"print\"Magnitude of electric field for plane wave in free space is \",round(E0,2),\"V/m\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Magnitude of electric field for plane wave in free space is 376.72 V/m\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg14:pg-236"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"E0=1e2 #maximum electric field in plane electromagnetic wave in Newton/coul.\n",
"c=3e8 #speed of light in m/sec\n",
"B0=E0/c \n",
"print\"Maximum magnetic field is \",round(B0,9),\"Tesla\"\n",
"print\"Maximum magnetic field will be in Z-direction.\"#this part is not printed in answer in book"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Maximum magnetic field is 3.33e-07 Tesla\n",
"Maximum magnetic field will be in Z-direction.\n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg15:pg-236"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"S=2*4.2e4/60 #energy flux per unit area per second at the earth surface\n",
"mu_0=4*round(math.pi,2)*1e-7 #permeability of free space in H/m\n",
"e0=8.85e-12 #permittivity of free space in F/m\n",
"EH=S\n",
"E_div_H=math.sqrt(mu_0/e0)\n",
"E=math.sqrt(E_div_H*EH)\n",
"H=EH/E\n",
"E0=round(E,1)*round(math.sqrt(2.),3)\n",
"H0=H*math.sqrt(2.)\n",
"print\"Amplitude of electric field is \",round(E0,1),\"V/m\"\n",
"print\"Amplitude of magnetic field is \",round(H0,3),\"A-turn m-1\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Amplitude of electric field is 1026.8 V/m\n",
"Amplitude of magnetic field is 2.726 A-turn m-1\n"
]
}
],
"prompt_number": 8
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg16:pg-236"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"P0=1000 #power in watt\n",
"r=2 #distance in meter\n",
"Sav=P0/(4*round(math.pi,2)*r**2)\n",
"mu_0=4*round(math.pi,2)*1e-7 #permeability of free space in H/m\n",
"e0=8.85e-12 #permittivity of free space in F/m\n",
"EH=Sav\n",
"E_div_H=math.sqrt(mu_0/e0)\n",
"E=math.sqrt(E_div_H*EH)\n",
"H=EH/E\n",
"print\"Average value of electric field intensity is \",round(E,2),\"V/m\"\n",
"print\"Average value of magnetic field intensity is \",round(H,2),\"A-turn m-1\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Average value of electric field intensity is 86.59 V/m\n",
"Average value of magnetic field intensity is 0.23 A-turn m-1\n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg17:pg-237"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"S=1.38 #energy flux in KW/m**2\n",
"c=3e8 #speed of light in m/sec\n",
"mu_0=4*math.pi*1e-7 #permeability of free space in H/m\n",
"E0=math.sqrt(2*mu_0*c*S*1e3)\n",
"B0=E0/c\n",
"print\"Peak value of electric field is \",round(E0*1e-3,2),\"KV/m\"\n",
"print\"Peak value of magnetic field is \",round(B0,7),\"Wb/m**2\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Peak value of electric field is 1.02 KV/m\n",
"Peak value of magnetic field is 3.4e-06 Wb/m**2\n"
]
}
],
"prompt_number": 11
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg18:pg-237"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"E0=100 #in Newton/coul.\n",
"A=1e-3 #area in m**2\n",
"l=100 #length in cm\n",
"e0=8.85e-12 #permittivity of free space in F/m\n",
"V=A*l*1e-2\n",
"U=e0*E0**2*V/2\n",
"print\"Energy contained in cylinder is \",U,\"Joule\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Energy contained in cylinder is 4.425e-11 Joule\n"
]
}
],
"prompt_number": 13
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg19:pg-238"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"E0=0.05 #amplitude of electric field strength in V/m\n",
"v=6 #frequency in MHz\n",
"c=3e8 #speed of light in m/sec\n",
"mu_0=4*math.pi*1e-7 #permeability of free space in H/m\n",
"e0=8.85e-12 #permittivity of free space in F/m\n",
"T=round(1/(v*1e6),9)\n",
"lamda=c/(v*1e6)\n",
"H0=E0/math.sqrt(mu_0/e0)\n",
"Sx_av=E0*round(H0,6)/2\n",
"print\"E=\",E0,\"*sin(\",\"{:.2e}\".format(2*math.pi/T),\"t -\",(2*round(math.pi,2)/lamda),\"x) V/m\"\n",
"print\"H=\",\"{:.2e}\".format(H0),\"*sin(\",\"{:.2e}\".format(2*math.pi/T),\"t -\",(2*round(math.pi,2)/lamda),\"x) A/m\" \n",
"print\"B=\",round(E0/c,12),\"*sin(\",\"{:.2e}\".format(2*math.pi/T),\"t -\",(2*round(math.pi,2)/lamda),\"x) Wb/m**2\" \n",
"print\"Average poynting vector S=\",Sx_av,\"Wb/m**2\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"E= 0.05 *sin( 3.76e+07 t - 0.1256 x) V/m\n",
"H= 1.33e-04 *sin( 3.76e+07 t - 0.1256 x) A/m\n",
"B= 1.67e-10 *sin( 3.76e+07 t - 0.1256 x) Wb/m**2\n",
"Average poynting vector S= 3.325e-06 Wb/m**2\n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg20:pg-239"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"lamda=7 #wavelength in mm\n",
"E0=42 #maximum magnitude of electric field in V/m\n",
"c=3e8 #speed of light in m/sec\n",
"print\"E=\",E0,\"*sin(2*pi*(ct-x)/\",lamda,\") V/m\"\n",
"print\"B=\",E0/c,\"*sin(2*pi*(ct-x)/\",lamda,\") Wb/m**2 \\nThe magnetic field is along Z-axis.\"\n",
"#unit is not mentioned in answer in book"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"E= 42 *sin(2*pi*(ct-x)/ 7 ) V/m\n",
"B= 1.4e-07 *sin(2*pi*(ct-x)/ 7 ) Wb/m**2 \n",
"The magnetic field is along Z-axis.\n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg21:pg-239"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"er=81 #relative permittivity of distilled water\n",
"e0=1 #let, permittivity of free space\n",
"mu_0=1 #let, permeability of free space\n",
"e=e0*er\n",
"c=3e8 #speed of light in m/sec\n",
"mu=mu_0#for distilled water\n",
"MU=math.sqrt((mu*e)/(mu_0*e0))\n",
"v=c/MU\n",
"print\"Refractive index is \",MU\n",
"print\"Velocity of light in distilled water is \",\"{:.2e}\".format(v),\"m/s\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Refractive index is 9.0\n",
"Velocity of light in distilled water is 3.33e+07 m/s\n"
]
}
],
"prompt_number": 17
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg23:pg-241"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"E0=7.5 #electric field intensity in KV/m\n",
"w=2e9 #angular frequency in rad/sec\n",
"c=3e8 #speed of light in m/sec\n",
"mu_0=4*round(math.pi,2)*1e-7 #permeability of free space in H/m\n",
"e0=8.85e-12 #permittivity of free space in F/m\n",
"f=w/(2*round(math.pi,2))\n",
"lamda=c/f\n",
"T=1/f\n",
"H0=E0*1e3/math.sqrt(mu_0/e0)\n",
"print\"Wavelength is \",lamda,\"m\"\n",
"print\"Frequency is \",round(f*1e-6,1),\"MHz\"\n",
"print\"Time period is \",T,\"sec\"\n",
"print\"Amplitude of magnetic field intensity is \",round(H0,2),\"A/m\"\n",
"print\"Therefore, Hz=\",round(H0,2),\"*cos( (%.e*t)-(beta*x)) A/m\"%w#unit is not printed in book"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Wavelength is 0.942 m\n",
"Frequency is 318.5 MHz\n",
"Time period is 3.14e-09 sec\n",
"Amplitude of magnetic field intensity is 19.91 A/m\n",
"Therefore, Hz= 19.91 *cos( (2e+09*t)-(beta*x)) A/m\n"
]
}
],
"prompt_number": 18
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg24:pg-241"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"mu_0=4*math.pi*1e-7 #permeability of free space in H/m\n",
"e0=8.854e-12 #permittivity of free space in F/m\n",
"#E=45*sin(6e8*pi*t-(2*pi*x))j+15*cos(6e8*pi*t-(2*pi*x))k volt/m (given equation) \n",
"#E=Ey*sin((w*t)-(beta*x))j + Ez*cos((w*t)-(beta*x))k (standard form)\n",
"#compairing given equation with above equation\n",
"pi=1 #let\n",
"beta=2*pi\n",
"w=6e8*pi\n",
"f=w/(2*pi)\n",
"n0=math.sqrt(mu_0/e0)\n",
"print\"Phase constant is %d*pi rad/s\"%beta\n",
"print\"Angular frequency is %.e*pi rad/s\"%w\n",
"print\"Frequency is %.e Hz\"%f\n",
"print\"Intrinsic impedance is %d Ohm\"%round(n0)\n",
"print\"Magnetic field is [0 %s*cos(6*pi*10**8*t-(2*pi*x)) %s*sin(6*pi*10**8*t-(2*pi*x))] A/m\"%(round(15/n0,4),round(45/n0,3)) #unit is not printed in book"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Phase constant is 2*pi rad/s\n",
"Angular frequency is 6e+08*pi rad/s\n",
"Frequency is 3e+08 Hz\n",
"Intrinsic impedance is 377 Ohm\n",
"Magnetic field is [0 0.0398*cos(6*pi*10**8*t-(2*pi*x)) 0.119*sin(6*pi*10**8*t-(2*pi*x))] A/m\n"
]
}
],
"prompt_number": 19
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg25:pg-242"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from sympy import symbols,diff,cos,sin\n",
"import math\n",
"x,y,B,Y=symbols('x y B Y')\n",
"Hz=(6*x*cos(B))+(12*y*sin(Y))\n",
"a=diff(Hz,y)\n",
"b=diff(-Hz,x)\n",
"c=0\n",
"d=array([a,b,c])\n",
"print\"J =\", d"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"J = [12*sin(Y) -6*cos(B) 0]\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg26:pg-244"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"A=1.3 #area in m**2\n",
"t=3 #time in hours\n",
"S=1.1 #intensity of sun rays in KW/m**2\n",
"c=3e8 #speed of light in m/sec\n",
"p=A*(t*3600)*(S*1000)/c\n",
"print\"Momentum is %se-4 Kg-m/s\"%(p*10000)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Momentum is 514.8e-4 Kg-m/s\n"
]
}
],
"prompt_number": 25
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg27:pg-245"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"S=10 #energy flux in watt/m**2\n",
"A=1 #area in m**2\n",
"t=1 #time in hour\n",
"c=3e8 #speed of light in m/sec\n",
"p=2*S*A*(t*3600)/c\n",
"F=2*S*A/c\n",
"print\"Momentum is %.1e Kg-m/s\"%p\n",
"print\"Force is %.2e N\"%F"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Momentum is 2.4e-04 Kg-m/s\n",
"Force is 6.67e-08 N\n"
]
}
],
"prompt_number": 26
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg29:pg-251"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"mu=4*math.pi*1e-7 #permeability in H/m\n",
"f=71.6 #frequency in MHz\n",
"sigma=3.54e7 #conductivity in siemens/m\n",
"d=1/sqrt(math.pi*f*1e6*mu*sigma)\n",
"print\"Depth of penetration is \",int(round(d*1e6)),\"micro meter\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Depth of penetration is 10 micro meter\n"
]
}
],
"prompt_number": 27
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg30:pg-251"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"f=3e6 #frequency in Hz\n",
"mu_r=1 \n",
"mu_0=4*round(math.pi,2)*1e-7 # in H/m\n",
"sigma=38e6 # in S/m\n",
"mu=mu_r*mu_0\n",
"d=1/math.sqrt(round(math.pi,2)*f*mu*sigma)\n",
"alpha=1/(d)\n",
"beta=alpha\n",
"magnitude=math.sqrt(alpha**2+beta**2)\n",
"angle=math.degrees(math.atan(beta/alpha))\n",
"v=2*round(math.pi,2)*f/round(beta)\n",
"print\"Skin depth is \",round(d*1e3,5),\"mm\"\n",
"print\"Propagation constant =[ %.4e , %s degree] m**-1\"%(magnitude,int(angle)) #in polar form\n",
"print\"Wave velocity is \",round(v,2),\"m/s\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Skin depth is 0.04716 mm\n",
"Propagation constant =[ 2.9987e+04 , 45 degree] m**-1\n",
"Wave velocity is 888.51 m/s\n"
]
}
],
"prompt_number": 30
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg31:pg-252"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"mu=4*math.pi*1e-7 # in H/m\n",
"e0=8.854e-12 # in F/m\n",
"e=70*e0\n",
"sigma=5\n",
"d=(2./sigma)*math.sqrt(e/mu)\n",
"alpha=1/round(d,4)\n",
"print\"skin depth is \",round(d,4),\"m\"\n",
"print\"Attenuation constant is \",round(alpha,2),\"Np/m\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"skin depth is 0.0089 m\n",
"Attenuation constant is 112.36 Np/m\n"
]
}
],
"prompt_number": 31
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg32:pg-253"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"import cmath\n",
"sigma=2e-3 #in S/m\n",
"e0=8.854e-12 #in F/m\n",
"e=80*e0\n",
"f=10 #in KHz\n",
"mu=4*math.pi*1e-7 #in H/m\n",
"ratio=sigma/(2*round(math.pi,2)*f*1e3*e)\n",
"\n",
"#since ratio= sigma/(w*e) = 44.96 >>1,therefore, medium is a good conductor.\n",
"#So calculations will be done considering medium as a good conductor.\n",
"\n",
"alpha=math.sqrt(2*math.pi*f*1e3*mu*sigma/2)\n",
"beta=int(alpha*1e5)*1e-5\n",
"magnitude=math.sqrt(alpha**2+beta**2)\n",
"angle=math.degrees(math.atan(beta/alpha))\n",
"ni=round(round(math.sqrt(2*math.pi*f*1e3*mu/sigma),2)/round(math.sqrt(2),2),3)*(1+1j)\n",
"lamda=2*round(math.pi,2)/beta\n",
"v=2*math.pi*f*1e3/beta\n",
"print\"Attenuation constant is %.2e neper/m\"%(int(alpha*1e5)*1e-5)\n",
"print\"Phase constant is %.2e rad/m\"%beta\n",
"print\"Propagation constant = [ %.3e , %.f degree] m**-1\"%(magnitude,angle)#in polar form(unit is not printed in book) \n",
"print\"Intrinsic impedance is \",ni,\"ohm\"\n",
"print\"Wavelength is %.2f m\"%lamda\n",
"print\"Velocity of wave is %.2e m/s\"%v"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Attenuation constant is 8.88e-03 neper/m\n",
"Phase constant is 8.88e-03 rad/m\n",
"Propagation constant = [ 1.256e-02 , 45 degree] m**-1\n",
"Intrinsic impedance is (4.454+4.454j) ohm\n",
"Wavelength is 707.21 m\n",
"Velocity of wave is 7.08e+06 m/s\n"
]
}
],
"prompt_number": 33
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg33:pg-254"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"f=100 #in MHz\n",
"mu_r=1\n",
"mu_0=4*round(math.pi,2)*1e-7 #in H/m\n",
"mu=mu_0*mu_r\n",
"sigma=58e6 #in S/m\n",
"alpha=math.sqrt(round(math.pi,2)*f*1e6*mu*sigma)\n",
"alpha=int(alpha/10)*10\n",
"beta=alpha\n",
"magnitude=math.sqrt(alpha**2+beta**2)\n",
"angle=math.degrees(math.atan(beta/alpha))\n",
"sqrt_j=45\n",
"ni=sqrt(2*round(math.pi,2)*f*1e6*mu/sigma)\n",
"v=2*round(math.pi,2)*f*1e6/beta\n",
"print\"Attenuation constant is %.4e neper/m\"%(int(alpha*1e5)*1e-5)\n",
"print\"Phase constant is %.4e rad/m\"%beta\n",
"print\"Propagation constant = [ %.4e , %.f degree] m**-1\"%(magnitude,angle)#in polar form(unit is not printed in book) \n",
"print\"Intrinsic impedance = [ %.3e , %s degree ] ohm\"%(ni,sqrt_j)#in polar form(unit is not printed in book)\n",
"print\"Velocity of wave is %.3f Km/s\"%(v/1e3)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Attenuation constant is 1.5124e+05 neper/m\n",
"Phase constant is 1.5124e+05 rad/m\n",
"Propagation constant = [ 2.1389e+05 , 45 degree] m**-1\n",
"Intrinsic impedance = [ 3.688e-03 , 45 degree ] ohm\n",
"Velocity of wave is 4.152 Km/s\n"
]
}
],
"prompt_number": 34
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Eg34:pg-255"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"mu=4*math.pi*1e-7 #in H/m\n",
"sigma=3.54e7 #in S/m\n",
"d=0.0664 #penetration depth in mm\n",
"f=1/(math.pi*mu*sigma*(d*1e-3)**2)\n",
"print\"Frequency is %.2f MHz\"%(f/1e6)\n",
"#answer is wrong in book because d=0.0644 is taken in calculation which is wrong(given d=0.0664 mm)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Frequency is 1.62 MHz\n"
]
}
],
"prompt_number": 36
}
],
"metadata": {}
}
]
}
|