Chapter 15:Parallel AC Circuits

Problem no:15.1, Page no:176

In [38]:
from __future__ import division

import math

#Initialization

V=240                     #Voltage in volts

#Resistance in Ohm

R1=400

R2=500

#Cal of current in each resistor

I1=V/R1

I2=V/R2

print "(a) I1=" ,I1,"A","I2=",I2,"A"

#Cal of total current

I=I1+I2

print "(b) I=",I,"A"

#Cal of Total resistance

R=V/I

print "(c) R=",int(R),"Ohm"

#Cal of Total power

P=I*V*math.cos(0)

print "(d) P=",int(P),"W"
(a) I1= 0.6 A I2= 0.48 A
(b) I= 1.08 A
(c) R= 222 Ohm
(d) P= 259 W

Problem no:15.2, Page no:176

In [39]:
from __future__ import division

import math

#Initialization

#Capacitance in muF

C1=30

C2=50

V=50         #Voltage in volts

f=400     #frequency in Hz

#Cal of current in each resistor

Xc1=1/(2*3.14*f*C1*10**-6)

I1=V/Xc1

Xc2=round(1/(2*3.14*f*C2*10**-6))

I2=V/Xc2

print "(a) I1=",round(I1,1),"A"

print "    I2=",I2,"A"

#Cal of total current

I=I1+I2

print "(b) I=",int(I),"A"

#Cal of Impedance

Z=V/I

print "(c) Z=",int(round(Z)),"Ohm"

#Cal of Total power

W=I*V*math.cos(math.radians(90))

print "(d) W=",int(W)
(a) I1= 3.8 A
    I2= 6.25 A
(b) I= 10 A
(c) Z= 5 Ohm
(d) W= 0

Problem no:15.12, Page no:183

In [40]:
from __future__ import division

import math

#Cal of resonance frquency

#Initialization

L=180                        #Inductance in muH

C=100                        #Capacitance in pF

#Calculation

L=L*(10**-6)

C=C*(10**-12)

fo=1/((2*math.pi)*(math.sqrt(L*C)))

fo=fo/10**6                   #Convert fo in MHz

print "fo=",round(fo,1),"MHz"
fo= 1.2 MHz