Chapter 11: Tuned Voltage mplifiers

Example 11.1 Page No.374

In [2]:
#Given
C=300*10**(-12)                                        #F, capacitance
L=220*10**(-6)                                          #H, inductance
R=20.0                                                             #Ohms, resistance

#Calculation
import math
fr=1/(2*math.pi*math.sqrt(L*C))                    #resonant frequency
#result
print " The Resonant Frequency, fr =  ",round(fr/10**3,0),"khz"

#(b) find  The Impedance at Resonance
#Calculation
Rr=R
#result
print " The Impedance at Resonance, Rr =   ",Rr,"ohm"

#(c) find  The Current at Resonance
V=10.0                                                             #V, voltage
#Calculation
I=V/R
#result
print " The Current at Resonance, I =   ",I,"A"

#(d)
#Calculation
fr=1/(2*math.pi*math.sqrt(L*C))
I=V/R
Xl=2*math.pi*fr*L                                        #reactance of inductor
Vl=I*Xl                                                      # Voltage across the Inductance
Xc=1/(2*math.pi*fr*C)                                 #reactance of capacitance
Vc=I*Xc                                                    # Voltage across the Capacitance,
Vr=I*R                                                       #Voltage across the Resistance

#result
print " Voltage across the Inductance, Vl =  ",round(Vl,0),"V"
print " Voltage across the Capacitance, Vc = ",round(Vc,0),"V"
print " Voltage across the Resistance, Vr =  ",round(Vr,0),"V"

 The Resonant Frequency, fr =   620.0 khz
 The Impedance at Resonance, Rr =    20.0 ohm
 The Current at Resonance, I =    0.5 A
 Voltage across the Inductance, Vl =   428.0 V
 Voltage across the Capacitance, Vc =  428.0 V
 Voltage across the Resistance, Vr =   10.0 V

Example 11.2 Page No.378

In [4]:
C=100*10**(-12)                                #F
L=100*10**(-6)                                 #H
R=10                                           #Ohms
V=100                                          #V

#Calculation
import math
fr=1/(2*math.pi*math.sqrt(L*C))        #Hz, resonant frequency
Xl=2*math.pi*fr*L                                #ohm,  inductive reactance
Il=V/Xl                                          #A, current in inductive branch
Xc=1/(2*math.pi*fr*C)                          #ohm, capacitance reactance
Ic=V/Xc                                         #A, current in capacitive branch 
Zp=L/(R*C)                                      #ohm , series impedance
I=V/Zp                                           #A, line current

#Result
print "fr= ",round(fr/10**3,0),"khz"
print "Il= ",Il,"A"
print "Ic= ",Ic,"A"
print "Zp= ",Zp,"ohm"
print "I=  ",I/10**(-3),"mA"

fr=  1592.0 khz
Il=  0.1 A
Ic=  0.1 A
Zp=  100000.0 ohm
I=   1.0 mA

Example 11.3 Page no. 379

In [5]:
import math
C=100*10**(-12)                            #F, capacitance
L=150*10**(-6)                              #H, inductance
R=15                                                 #Ohms, resistance

#Calculation
fr=1/(2*math.pi*math.sqrt(L*C))
Zp=L/(R*C)
Q=2*math.pi*fr*L/R
df=fr/Q                                            #Bandwidth

#The Result
print " Impedance, Zp=  ",Zp/10**3,"kohm"
print " Quality Factor, Q=  ",round(Q,1)
print " Bandwidth, df=  ",round(df/10**3,2),"khz"

 Impedance, Zp=   100.0 kohm
 Quality Factor, Q=   81.6
 Bandwidth, df=   15.92 khz