Operational Amplifier and Its Applications MCQs

Question 1

The pulsating d.c. appliedto power amplifier causes

Accepted Answer

hum in the circuit

Answer

burning of transistor

Answer

excessive forward voltage

Answer

none of the above

Question 2

The most costly couping is ____ coupling.

Accepted Answer

transformer

Answer

RC

Answer

direct

Answer

impedance

Question 3

In an LC circuit, when the capacitor energy is maximum, the inductor energy is must use

Accepted Answer

minimum

Answer

maximum

Answer

half-way between maximum and minimum

Answer

none of the above

Question 4

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

Accepted Answer

inversely proportional to square root of

Answer

proportional to square

Answer

directly proportional to

Answer

independent of the values of

Question 5

In a phase shift oscillator, the frequency determining elements are

Accepted Answer

R and C

Answer

L and C

Answer

R, Land C

Answer

none of the above

Question 6

A wien bridge oscillator uses ____ feedback.

Accepted Answer

none of the above

Answer

only positive

Answer

only negative both positive and negative

Question 7

The piezoelectric effect in a crystal is

Accepted Answer

a voltage developed because of mechanical stress

Answer

a change in resistance because of temperature

Answer

a change of frequency because of temperature

Answer

none of the above

Question 8

A second condition for oscillations IS

Accepted Answer

a gain of 1 around the feedback loop

Answer

no gain around the feedback loop

Answer

the attenuation of the feedback circuit must be one-third

Answer

the feedback circuit must be capacitive

Question 9

In a certain oscillator, A, = 50. The attenuation of the feedback circuit must be

Accepted Answer

0.02

Answer

1

Answer

0.01

Answer

10