Explore topic-wise MCQs in Electrical Engineering Questions.

This section includes 38 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering Questions knowledge and support exam preparation. Choose a topic below to get started.

1.

If the power rating of a transistor is 1W and collector current is 100mA, then maximum allowable collector voltage is________________?
A. 1V
B. 100V
C. 20V
D. 10V
Answer» E.
Discussion
2.

The output transformer used in a power amplifier is a _____________ transformer?
A. 1:1 ratio
B. Step-up
C. Step-down
D. None of the above
Answer» D. None of the above
Discussion
3.

The pulsating d.c. applied to power amplifier causes________________?
A. Burning of transistor
B. Hum in the circuit
C. Excessive forward voltage
D. None of the above
Answer» C. Excessive forward voltage
Discussion
4.

________________ coupling is generally employed in power amplifiers?
A. Transformer
B. RC
C. direct
D. Impedance
Answer» B. RC
Discussion
5.

The maximum efficiency of transformer coupled class A power amplifier is _______________?
A. 30%
B. 50%
C. 80%
D. 45%
Answer» C. 80%
Discussion
6.

If the gain versus frequency curve of a transistor amplifier is not flat, then there is distortion ?
A. Amplitude
B. Intermodulation
C. Frequency
D. None of the above
Answer» D. None of the above
Discussion
7.

The output stage of a multistage amplifier is also called _________________-?
A. Mixer stage
B. Power stage
C. Detector stage
D. F stage
Answer» C. Detector stage
Discussion
8.

A class A power amplifier uses _________________?
A. Two transistors
B. Three transistors
C. One transistor
D. None of the above
Answer» D. None of the above
Discussion
9.

The maximum efficiency of resistance loaded class A power amplifier is _________________?
A. 5%
B. 50%
C. 30%
D. 25%
Answer» E.
Discussion
10.

Power amplifiers handle ______________ signals compare to voltage amplifiers?
A. Small
B. Very small
C. Large
D. None of the above
Answer» D. None of the above
Discussion
11.

Class_____________ power amplifier has the highest collector efficiency ?
A. C
B. A
C. B
D. AB
Answer» B. A
Discussion
12.

The most important consideration in power amplifier is __________________?
A. Biasing the circuit
B. Collector efficiency
C. To keep the transformer cool
D. None of the above
Answer» C. To keep the transformer cool
Discussion
13.

The maximum a.c. power output from a class A power amplifier is 10 W. What should be the minimum power rating of the transistor used ?
A. 10 W
B. 15 W
C. 5 W
D. 20 W
Answer» E.
Discussion
14.

In class A operation, the operating point is generally located_____________of the d.c. load line?
A. At cut off point
B. At the middle
C. At saturation point
D. None of the above
Answer» C. At saturation point
Discussion
15.

The class B push-pull circuit can deliver 100 W of a.c. output power. What should be the minimum power rating of each transistor ?
A. 20 W
B. 40 W
C. 10 W
D. 80 W
Answer» B. 40 W
Discussion
16.

Power amplifiers generally use transformer coupling because transformer permits______________?
A. Cooling of the circuit
B. Impedance matching
C. Distortionless output
D. Good frequency response
Answer» C. Distortionless output
Discussion
17.

A transformer coupled class A power amplifier has a load of 100 O on the secondary. If the turn ratio is 10:1, what is the value of load appearing on the primary?
A. 5 kO
B. 20 kO
C. 100 kO
D. 10 kO
Answer» E.
Discussion
18.

Transformer coupling can be used in______________amplifiers?
A. Either power or voltage
B. Only power
C. Only voltage
D. None of the above
Answer» B. Only power
Discussion
19.

The disadvantage of impedance matching is that it _______________?
A. Gives distorted output
B. Gives low power output
C. Requires a transformer
D. None of the above
Answer» B. Gives low power output
Discussion
20.

An AF amplifier is shielded to ________________?
A. Keep the amplifier cool
B. Protect from rusting
C. Prevent induction due to stray magnetic fields
D. None of the above
Answer» D. None of the above
Discussion
21.

Class C amplifiers are used as ___________________?
A. AF amplifiers
B. Detectors
C. amplifiers
D. None of the above
Answer» D. None of the above
Discussion
22.

The maximum collector efficiency of class B operation is ________________?
A. 50%
B. 90%
C. 15%
D. 5%
Answer» E.
Discussion
23.

The most costly coupling is _______________ coupling?
A. RC
B. Direct
C. Impedance
D. Transformer
Answer» E.
Discussion
24.

If a transistor is operated in such a way that output current flows for 60o of the input signal, then it is ______________ operation?
A. Class A
B. Class B
C. Class C
D. None of the above
Answer» D. None of the above
Discussion
25.

The driver stage usually employs_________________?
A. Class A power amplifier
B. Push-pull amplifier
C. Class C amplifier
D. None of the above
Answer» B. Push-pull amplifier
Discussion
26.

The push-pull circuit must use ______________ operation?
A. Class A
B. Class C
C. Class B
D. Class AB
Answer» D. Class AB
Discussion
27.

The output signal voltage and current of a power amplifier are 5V and 200 mA; the values being r.m.s. What is the power output ?
A. 1 W
B. 2 W
C. 4 W
D. None of the above
Answer» B. 2 W
Discussion
28.

For the same a.c. power output as above, what should be the minimum power rating of transistor for class B operation?
A. 10 W
B. 4 W
C. 8 W
D. None of the above
Answer» C. 8 W
Discussion
29.

A power amplifier has comparatively __________________ ß ?
A. Small
B. Large
C. Very large
D. None of the above
Answer» B. Large
Discussion
30.

A 2-transistor class B power amplifier is commonly called ______________ amplifier?
A. Dual
B. Push-pull
C. Symmetrical
D. Differential
Answer» C. Symmetrical
Discussion
31.

A class A power amplifier is sometimes called______________amplifier?
A. Symmetrical
B. Single-ended
C. Reciprocating
D. Differential
Answer» C. Reciprocating
Discussion
32.

Low efficiency of a power amplifier results in_________________?
A. Low forward bias
B. Less battery consumption
C. More battery consumption
D. None of the above
Answer» D. None of the above
Discussion
33.

Class _____________ operation gives the maximum distortion?
A. A
B. B
C. C
D. AB
Answer» D. AB
Discussion
34.

The size of a power transistor is made considerably large to________________?
A. Provide easy handling
B. Dissipate heat
C. Facilitate connections
D. None of the above
Answer» C. Facilitate connections
Discussion
35.

The output stage of a multistage amplifier usually employs______________?
A. Push-pull amplifier
B. Preamplifier
C. Class A power amplifier
D. None of the above
Answer» B. Preamplifier
Discussion
36.

The output stage of a multistage amplifier usually employs _________________?
A. Push-pull amplifier
B. Preamplifier
C. Class A power amplifier
D. None of the above
Answer» B. Preamplifier
Discussion
37.

If the zero signal dissipation of a transistor is 1W, then power rating of the transistor should be at least___________________?
A. 5 W
B. 33 W
C. 75 W
D. 1 W
Answer» E.
Discussion
38.

When a transistor is cut off _________________?
A. Maximum voltage appears across transistor
B. Maximum current flows
C. Maximum voltage appears across load
D. None of the above
Answer» B. Maximum current flows
Discussion