51. The Thevenin voltage of a dead circuit is zero volts.
A. True
B. False
Answer: A
In the case of the dead network, there are no independent sources available in the electrical circuit. The Thevenin voltage of the circuit is zero because no force is available to drive the current in the circuit.
52. During the open circuit condition, the current is equal to ______
A. 1 A
B. 0 A
C. 4 A
D. 7 A
Answer: B
During the open circuit condition, the current is equal to zero amperes.
According to Ohm’s law, I=V/R=0 A.
The value of the voltage can be positive, negative, or zero.
53. The minimum value of the impedance in the case of the series RLC network is ___________
A. R
B. 0
C. Xl
D. Xc
Answer: A
The minimum value of the series impedance in the case of the series RLC network is R. During resonance condition
Xl=Xc
Z=(R2+(Xl-XC)2).5=R.
54. Calculate the quality factor for the purely inductive coil.
A. inf
B. 10
C. 3
D. 6
Answer: A
The quality factor is defined as the ratio of the reactive power to the active power consumed. The purely inductive coil always absorbs reactive power. The value of active power consumed is 0.
Quality factor=Q/0=inf.
55. Calculate the quality factor for the pure capacitor.
A. inf
B. 0
C. 1
D. 2
Answer: A
The quality factor is defined as the ratio of the reactive power to the active power consumed. The pure capacitor always absorbs reactive power. The value of active power consumed is 0.
Quality factor=Q/0=inf.
56. Calculate the equivalent inductance when n inductors are connected in a series of values L.
A. n2L H
B. nL H
C. .5L H
D. 2 H
Answer: B
When two inductors are connected in series their equivalent inductance is equal to the sum of the individual inductances.
Leq=L+L+…..+n times L=nL H.
57. Calculate the equivalent resistance when two resistances are connected in a series of values 12 Ω, and 10 Ω.
A. 32 Ω
B. 22 Ω
C. 47 Ω
D. 17 Ω
Answer: B
When two resistances are connected in series their equivalent resistance is equal to the sum of the individual resistances.
Req=R1+R2=22 Ω.
58. Reactive power is positive in the case of the inductor.
A. True
B. False
Answer: A
The reactive power is defined as the product of the voltage, current, and sine of the difference between the phase angle of voltage and current. In the case of an inductor, the voltage leads to the current. The value of sine is positive and reactive power is positive.
