Explore topic-wise MCQs in Electrical Engineering.

This section includes 29 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

The piezoelectric effect in a crystal is ___________%!

A. A voltage developed because of mechanical stress
B. A change in resistance because of temperature
C. A change in frequency because of temperature
D. None of the above
Answer» B. A change in resistance because of temperature
2.

In an LC oscillator, if the value of L is increased four times, the frequency of oscillations is ___________%!

A. Increased 2 times
B. Decreased 4 times
C. Increased 4 times
D. Decreased 2 times
Answer» E.
3.

A second condition for oscillations is ___________%!

A. A gain of 1 around the feedback loop
B. No gain around the feedback loop
C. The attention of the feedback circuit must be one-third
D. The feedback circuit must be capacitive
Answer» B. No gain around the feedback loop
4.

*$_The crystal oscillator frequency is very stable due to ___________ of the crystal?

A. Rigidity
B. Vibrations
C. Low Q
D. High Q
Answer» E.
5.

*/*_An oscillator employs ___________ feedback?

A. Positive
B. Negative
C. Neither positive nor negative
D. Data insufficient
Answer» B. Negative
6.

*/*_In an LC circuit, when the capacitor is maximum, the inductor energy is ___________?

A. Minimum
B. Maximum
C. Half-way between maximum and minimum
D. None of the above
Answer» B. Maximum
7.

*/*_In a phase shift oscillator, the frequency determining elements are ___________?

A. L and C
B. R, L and C
C. R and C
D. None of the above
Answer» D. None of the above
8.

*/*_In a Wien-bridge oscillator, if the resistances in the positive feedback circuit are decreased, the frequency ___________?

A. Remains the same
B. Decreases
C. Increases
D. Insufficient data
Answer» D. Insufficient data
9.

%_Hartley oscillator is commonly used in ____________%

A. Radio receivers
B. Radio transmitters
C. TV receivers
D. None of the above
Answer» B. Radio transmitters
10.

__The signal generator generally used in the laboratories is ___________ oscillator__

A. Wien-bridge
B. Hartely
C. Crystal
D. Phase shift
Answer» B. Hartely
11.

__An important limitation of a crystal oscillator is _____________

A. Its low output
B. Its high Q
C. Less availability of quartz crystal
D. Its high output
Answer» B. Its high Q
12.

__An oscillator converts _____________

A. a.c. power into d.c. power
B. d.c. power into a.c. power
C. mechanical power into a.c. power
D. none of the above
Answer» C. mechanical power into a.c. power
13.

__If the crystal frequency changes with temperature, we say that crystal has ___________ temperature coefficient__

A. Positive
B. Zero
C. Negative
D. None of the above
Answer» B. Zero
14.

_In a certain oscillator Av = 50. The attention of the feedback circuit must be ___________$?

A. 1
B. 1
C. 10
D. 2
Answer» E.
15.

In a phase shift oscillator, we use ___________ RC sections$?

A. Two
B. Three
C. Four
D. None of the above
Answer» C. Four
16.

The application where one would most likely find a crystal oscillator is ___________$?

A. Radio receiver
B. Radio transmitter
C. AF sweep generator
D. None of the above
Answer» C. AF sweep generator
17.

One condition for oscillation is ___________$?

A. A phase shift around the feedback loop of 180°
B. A gain around the feedback loop of one-third
C. A phase shift around the feedback loop of 0°
D. A gain around the feedback loop of less than 1
Answer» D. A gain around the feedback loop of less than 1
18.

The Q of the crystal is of the order of ___________$?

A. 100
B. 1000
C. 50
D. More than 10,000
Answer» E.
19.

Quartz crystal is most commonly used in crystal oscillators because ___________$?

A. It has superior electrical properties
B. It is easily available
C. It is quite inexpensive
D. None of the above
Answer» B. It is easily available
20.

Quartz crystal is most commonly used in crystal oscillators because ___________?

A. It has superior electrical properties
B. It is easily available
C. It is quite inexpensive
D. None of the above
Answer» B. It is easily available
21.

An LC oscillator cannot be used to produce ___________ frequencies

A. High
B. Audio
C. Very low
D. Very high
Answer» D. Very high
22.

___________ is a fixed frequency oscillator

A. Phase-shift oscillator
B. Hartely-oscillator
C. Colpitt's oscillator
D. Crystal oscillator
Answer» E.
23.

An oscillator differs from an amplifier because it

A. Has more gain
B. Requires no input signal
C. Requires no d.c. supply
D. Always has the same input
Answer» C. Requires no d.c. supply
24.

For an oscillator to properly start, the gain around the feedback loop must initially be

A. 1
B. Greater than 1
C. Less than 1
D. Equal to attenuation of feedback circuit
Answer» C. Less than 1
25.

In an LC oscillator, the frequency of oscillator is ___________ L or C.

A. Proportional to square of
B. Directly proportional to
C. Independent of the values of
D. Inversely proportional to square root of
Answer» E.
26.

An oscillator produces___________ oscillations

A. Damped
B. Undamped
C. Modulated
D. None of the above
Answer» C. Modulated
27.

In an LC transistor oscillator, the active device is ___________

A. LC tank circuit
B. Biasing circuit
C. Transistor
D. None of the above
Answer» D. None of the above
28.

A Wien bridge oscillator uses ___________ feedback

A. Only positive
B. Only negative
C. Both positive and negative
D. None of the above
Answer» D. None of the above
29.

In Colpitt's oscillator, feedback is obtained ___________

A. By magnetic induction
B. By a tickler coil
C. From the centre of split capacitors
D. None of the above
Answer» D. None of the above