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{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"CHAPTER 17 - AC COMMUTATOR MOTORS"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example E1 - Pg 393"
]
},
{
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"input": [
"#Caption:Find (a)Speed (b)Power factor of motor\n",
"#Exa:17.1\n",
"import math\n",
"r=25.#Resistance of motor(in ohms)\n",
"P=2.#Number of poles\n",
"l=0.4#Inductance of motor(in henry)\n",
"n=1800.#Speed of motor(in r.p.m)\n",
"V=230.#Voltage supplied(in volts)\n",
"Il=1.#Load current(in A)\n",
"f=50.#Frequency(in hertz)\n",
"fr=(P*n)/120.\n",
"Eb=V-(r*Il)\n",
"Er=Eb/fr\n",
"fac=(math.sqrt((V**2.)-((Il*2.*(math.pi)*f*l)**2.))-(Il*r))/Er\n",
"n=fac*(120./P)\n",
"print '%s %.f' %('(a)Speed(in rpm)=',n)\n",
"pf=math.sqrt((V**2.)-((Il*2.*(math.pi)*f*l)**2.))/V\n",
"print '%s %.2f' %('(b)Power factor=',pf)"
],
"language": "python",
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"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"(a)Speed(in rpm)= 1472\n",
"(b)Power factor= 0.84\n"
]
}
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"prompt_number": 1
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"metadata": {}
}
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|
