BJT Amplifiers and Oscillators MCQs

Question 1

CC configuration is used for impedance matching because its

Accepted Answer

input impedance is very high

Answer

input impedance is low

Answer

output impedance is very low

Answer

one of the above

Question 2

A radio revceiver has of amplification.

Accepted Answer

Answer

one stage

Answer

two stages

Answer

three stages (d) more than three stages

Question 3

The best frequency response of coupling.

Accepted Answer

direct

Answer

RC

Answer

transformer

Answer

none of the above

Question 4

In RC coupling, the value of coupling capacitor is about

Accepted Answer

10 pF

Answer

100 pF

Answer

0.1 pF

Answer

0.01 1.1F

Question 5

The noise factor of an ideal amplifier expressed in db is

Accepted Answer

0

Answer

1

Answer

0.1

Answer

10

Question 6

Transformer coupling provides high efficiency because

Accepted Answer

d.c. resistance is low

Answer

collector voltage is stepped up

Answer

collector voltage is stepped down

Answer

none of the above

Question 7

The total gain of a multistage amplifier is less than the product of the gains of individual stages due to

Accepted Answer

loading effect of next stage

Answer

power loss in the coupling device

Answer

the use of many transistors

Answer

the use of many capacitors

Question 8

If the power level of an amplifier reduces to half, the db gain will fall by

Accepted Answer

3 db

Answer

0.5 db

Answer

2 db

Answer

10 db

Question 9

An amplifier receives 0.1 W of input signal and delivers 15W of signal power. What is the power gain in db?

Accepted Answer

21.8 db

Answer

14.6 db

Answer

9.5 db

Answer

17.4 db