#Caption:Find (a)Speed (b)Power factor of motor
#Exa:17.1
import math
r=25.#Resistance of motor(in ohms)
P=2.#Number of poles
l=0.4#Inductance of motor(in henry)
n=1800.#Speed of motor(in r.p.m)
V=230.#Voltage supplied(in volts)
Il=1.#Load current(in A)
f=50.#Frequency(in hertz)
fr=(P*n)/120.
Eb=V-(r*Il)
Er=Eb/fr
fac=(math.sqrt((V**2.)-((Il*2.*(math.pi)*f*l)**2.))-(Il*r))/Er
n=fac*(120./P)
print '%s %.f' %('(a)Speed(in rpm)=',n)
pf=math.sqrt((V**2.)-((Il*2.*(math.pi)*f*l)**2.))/V
print '%s %.2f' %('(b)Power factor=',pf)