{
"metadata": {
"name": "",
"signature": "sha256:544912fca601384def1f6da3b02bc7431b47e0d8f9efa5f2e7d2a367448daaa6"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Magnetic Properties"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.1, Page number 119"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"H=6.5*10**-4; #magnetic field in T\n",
"M=1.4; #field with iron\n",
"\n",
"#Calculation\n",
"chi=M/H;\n",
"mew_r=1+chi;\n",
"mew_r=math.ceil(mew_r*10**2)/10**2; #rounding off to 2 decimals\n",
"\n",
"#Result\n",
"print(\"relative permeability of iron is\",mew_r);\n",
"\n",
"#answer given in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('relative permeability of iron is', 2154.85)\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.2, Page number 119"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"H=220; #field in amp/m\n",
"M=3300; #magnetisation in amp/m\n",
"\n",
"#Calculation\n",
"chi=M/H;\n",
"mew_r=1+chi;\n",
"\n",
"#Result\n",
"print(\"relative permeability is\",mew_r);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('relative permeability is', 16.0)\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.3, Page number 120 *****"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"r=5.29*10**-11; #radius of orbit in m\n",
"B=2; #applied field in Tesla\n",
"e=1.602*10**-19; #charge of electron in coulomb\n",
"m=9.108*10**-31; #mass of electron in kg\n",
"\n",
"#Calculation\n",
"mew=(e**2)*(r**2)*B/(4*m);\n",
"\n",
"#Result\n",
"print(\"magnetic moment in Am^2 is\",mew);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('magnetic moment in Am^2 is', 3.94260574090909e-29)\n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.4, Page number 120"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"\n",
"#Variable decleration\n",
"chi=0.5*10**-5; #susceptibility \n",
"H=10**6; #field strength in amp/m\n",
"\n",
"#Calculation\n",
"mew_0=4*math.pi*10**-7;\n",
"I=chi*H;\n",
"B=mew_0*(I+H);\n",
"B=math.ceil(B*10**3)/10**3; #rounding off to 3 decimals\n",
"\n",
"#Result\n",
"print(\"intensity of magnetisation in Amp/m is\",I);\n",
"print(\"flux density in Weber/m^2 is\",B);\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('intensity of magnetisation in Amp/m is', 5.0)\n",
"('flux density in Weber/m^2 is', 1.257)\n"
]
}
],
"prompt_number": 7
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.5, Page number 120"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"e=2.86; #edge in armstrong\n",
"e=e*10**-10; #edge in m\n",
"Is=1.76*10**6; #magnetisation in amp/m\n",
"mewB=9.27*10**-24; #1 bohr magneton in amp m^2\n",
"\n",
"#Calculation\n",
"N=2/(e**3); #density per m^3\n",
"mewbar=Is/N;\n",
"mew_bar=mewbar/mewB;\n",
"mew_bar=math.ceil(mew_bar*10**3)/10**3; #rounding off to 3 decimals\n",
"\n",
"#Result\n",
"print(\"average dipole moment in mewB is\",mew_bar);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('average dipole moment in mewB is', 2.221)\n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.6, Page number 121 ***"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"H=10**6; #magnetic field in amp/m\n",
"chi=1.5*10**-3; #susceptibility\n",
"\n",
"#Calculation\n",
"mew_0=4*math.pi*10**-7;\n",
"M=chi*H;\n",
"B=mew_0*(M+H);\n",
"\n",
"#Result\n",
"print(\"magnetisation in Amp/m is\",M);\n",
"print(\"flux density in Tesla is\",B);\n",
"\n",
"#answer for flux density given in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('magnetisation in Amp/m is', 1500.0)\n",
"('flux density in Tesla is', 1.258522017028071)\n"
]
}
],
"prompt_number": 11
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.7, Page number 121"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"chi=3.7*10**-3; #susceptibility \n",
"H=10**4; #field strength in amp/m\n",
"\n",
"#Calculation\n",
"mew_0=4*math.pi*10**-7;\n",
"M=chi*H;\n",
"B=mew_0*(M+H);\n",
"B=math.ceil(B*10**5)/10**5; #rounding off to 5 decimals\n",
"\n",
"#Result\n",
"print(\"magnetisation in Amp/m is\",M);\n",
"print(\"flux density in Weber/m^2 is\",B);\n",
"\n",
"#answer for flux density given in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('magnetisation in Amp/m is', 37.0)\n",
"('flux density in Weber/m^2 is', 0.01262)\n"
]
}
],
"prompt_number": 13
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.8, Page number 121"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"r=0.052*10**-9; #radius of orbit in m\n",
"B=1; #magnetic field in Wb/m^2\n",
"e=1.6*10**-19; #charge of electron in coulomb\n",
"m=9.1*10**-31; #mass of electron in kg\n",
"\n",
"#Calculation\n",
"dmew=(e**2)*(r**2)*B/(4*m);\n",
"\n",
"#Result\n",
"print(\"magnetic moment in Am^2 is\",dmew);\n",
"\n",
"#answer given in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('magnetic moment in Am^2 is', 1.901714285714286e-29)\n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.9, Page number 122"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"\n",
"#Variable decleration\n",
"chi=-0.5*10**-5; #susceptibility \n",
"H=9.9*10**4; #field strength in amp/m\n",
"\n",
"#Calculation\n",
"mew_0=4*math.pi*10**-7;\n",
"I=chi*H;\n",
"B=mew_0*H*(1+chi);\n",
"I=math.ceil(I*10**4)/10**4; #rounding off to 4 decimals\n",
"B=math.ceil(B*10**4)/10**4; #rounding off to 4 decimals\n",
"\n",
"#Result\n",
"print(\"intensity of magnetisation in Amp/m is\",I);\n",
"print(\"flux density in Weber/m^2 is\",B);\n",
"\n",
"#answer for flux density given in the book is wrong "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('intensity of magnetisation in Amp/m is', -0.495)\n",
"('flux density in Weber/m^2 is', 0.1245)\n"
]
}
],
"prompt_number": 18
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.10, Page number 122"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"r=6.1*10**-11; #radius of H atom in m\n",
"new=8.8*10**15; #frequency in rev/sec\n",
"e=1.6*10**-19;\n",
"\n",
"#Calculation\n",
"mew0=4*math.pi*10**-7;\n",
"i=e*new;\n",
"B=(mew0*i)/(2*r);\n",
"mew=i*math.pi*(r**2);\n",
"i=math.ceil(i*10**7)/10**7; #rounding off to 7 decimals\n",
"B=math.ceil(B*10**3)/10**3; #rounding off to 3 decimals\n",
"\n",
"#Result\n",
"print(\"current in amp is\",i);\n",
"print(\"magnetic induction in weber/m^2 is\",B);\n",
"print(\"dipole moment in amp m^2 is\",mew);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('current in amp is', 0.0014081)\n",
"('magnetic induction in weber/m^2 is', 14.503)\n",
"('dipole moment in amp m^2 is', 1.645933169972273e-23)\n"
]
}
],
"prompt_number": 22
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.11, Page number 123"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"Is=1.96*10**6; #saturation magnetisation in amp/m\n",
"a=3; #cube edge of iron in armstrong\n",
"a=a*10**-10; #cube edge of iron in m\n",
"mew_b=9.27*10**-24; #bohr magneton in amp/m^2\n",
"n=2; #number of atoms per unit cell\n",
"\n",
"#Calculation\n",
"N=n/(a**3);\n",
"mewbar=Is/N;\n",
"mew_ab=mewbar/mew_b;\n",
"mew_ab=math.ceil(mew_ab*10**4)/10**4; #rounding off to 4 decimals\n",
"\n",
"#Result\n",
"print(\"average number of Bohr magnetons in bohr magneton per atom is\",mew_ab);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('average number of Bohr magnetons in bohr magneton per atom is', 2.8544)\n"
]
}
],
"prompt_number": 24
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.12, Page number 123"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"I=3000; #magnetisation in amp/m\n",
"B=0.005; #flux density in weber/m^2\n",
"\n",
"#Calculation\n",
"mew0=4*math.pi*10**-7;\n",
"H=(B/mew0)-I;\n",
"mew_r=(I/H)+1;\n",
"H=math.ceil(H*10**3)/10**3; #rounding off to 3 decimals\n",
"mew_r=math.ceil(mew_r*10**3)/10**3; #rounding off to 3 decimals\n",
"\n",
"#Result\n",
"print(\"magnetic force in amp/m is\",H);\n",
"print(\"relative permeability is\",mew_r);\n",
"\n",
"#answer given in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('magnetic force in amp/m is', 978.874)\n",
"('relative permeability is', 4.065)\n"
]
}
],
"prompt_number": 28
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.13, Page number 124"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"H=1800; #magnetising field in amp/m\n",
"phi=3*10**-5; #magnetic flux in weber\n",
"A=0.2; #cross sectional area in cm^2\n",
"\n",
"#Calculation\n",
"A=A*10**-4; #cross sectional area in m^2\n",
"B=phi/A;\n",
"mew=B/H;\n",
"mew=math.ceil(mew*10**8)/10**8 #rounding off to 8 decimals\n",
"\n",
"#Result\n",
"print(\"the permeability in Henry/m is\",mew);\n",
"\n",
"#answer given in the book is wron"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('the permeability in Henry/m is', 0.00083334)\n"
]
}
],
"prompt_number": 31
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.14, Page number 124 ********************"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"r=0.04; #radius of circular loop in m\n",
"i=1000; #current in mA\n",
"i=i*10**-3; #current in amp\n",
"B=10**-3; #magnetic flux density in Wb/m^2\n",
"theta=45; #angle in degrees\n",
"\n",
"#Calculation\n",
"A=math.pi*(r**2);\n",
"mew=i*A;\n",
"tow=i*B*math.cos(theta);\n",
"mew=math.ceil(mew*10**6)/10**6 #rounding off to 6 decimals\n",
"\n",
"#Result\n",
"print(\"the magnetic dipole moment in amp m^2 is\",mew);\n",
"print(\"the torque in Nm is\",tow);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('the magnetic dipole moment in amp m^2 is', 0.005027)\n",
"('the torque in Nm is', 0.0005253219888177298)\n"
]
}
],
"prompt_number": 36
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.15, Page number 125"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"\n",
"#Variable decleration\n",
"A=100; #area of hysteris loop in m^2\n",
"B=0.01; #flux density in wb/m^2\n",
"H=40; #magnetic field in amp/m\n",
"M=7650; #atomic weight in kg/m^3\n",
"\n",
"#Calculation\n",
"hl=A*B*H;\n",
"\n",
"#Result\n",
"print(\"the hysterisis loss per cycle in J/m^3 is\",hl);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('the hysterisis loss per cycle in J/m^3 is', 40.0)\n"
]
}
],
"prompt_number": 38
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 4.17, Page number 125"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
" \n",
"#import module\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable decleration\n",
"hl=200; #hysterisis loss per cycle in J/m^3\n",
"M=7650; #atomic weight in kg/m^3\n",
"m=100; #magnetisation cycles per second\n",
"\n",
"#Calculation\n",
"hpl=hl*m;\n",
"pl=hpl/M;\n",
"pl=math.ceil(pl*10**4)/10**4 #rounding off to 4 decimals\n",
"\n",
"#Result\n",
"print(\"hysterisis power loss per second in watt/m^3 is\",hpl);\n",
"print(\"the power loss in watt/kg is\",pl); \n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"('hysterisis power loss per second in watt/m^3 is', 20000)\n",
"('the power loss in watt/kg is', 2.6144)\n"
]
}
],
"prompt_number": 40
},
{
"cell_type": "code",
"collapsed": false,
"input": [],
"language": "python",
"metadata": {},
"outputs": []
}
],
"metadata": {}
}
]
}