Chapter8 - Measurement of Power

Exa 8.1 page 189

In [1]:
ZL=220/2 
print "Load impedance=%.1f ohm"%(ZL)
Z_total=220/4 
print "Impedance of the combination=%.2f ohm"%(Z_total)
I1=2 
I2=2.5 
I3=4 
P=(Z_total/2)*(I3**2-I1**2-I2**2) 
print "Power absorbed by load=%.2f W"%(P)
pf=P/(220*2**2) 
print "power factor of load=%.2f"%(pf)

Load impedance=110.0 ohm
Impedance of the combination=55.00 ohm
Power absorbed by load=155.25 W
power factor of load=0.18

Exa 8.2 page 189

In [2]:
from __future__ import division
I=125/10 
ZL=50/I 
print "Load impedance = %.1f ohm"%(ZL)
Z_total=150/I 
print "Impedance of the combination = %.2f ohm"%(Z_total)
I1=125 
I2=50 
I3=150 
P=(1/(2*10))*(I3**2-I1**2-I2**2) 
print "Power absorbed by load = %.2f W"%(P)
Pr=I**2*10 
print "Power consumed by the resistor = %.2f W"%(Pr)
pf=P/(50*I) 
print "power factor of load = %.2f"%(pf)

Load impedance = 4.0 ohm
Impedance of the combination = 12.00 ohm
Power absorbed by load = 218.75 W
Power consumed by the resistor = 1562.50 W
power factor of load = 0.35