Electronics and Communications TNPSC Group 1 Questions

Electronics and Communications MCQ Questions

13.
The common emitter configuration is more preferred than the commonbase configuration because the common emitter configuration gives
A.
low current gain, low voltage gain and low power gain
B.
low current gain, high voltage gain and low power gain
C.
high current gain, high voltage gain and highpower gain
D.
high current gain, high voltage gain and low power gain
ANSWER :
C. high current gain, high voltage gain and highpower gain
14.
Transformers are used to
A.
Convert AC into DC
B.
Convert DC into AC
C.
step up DC voltage
D.
step up or step down AC voltage
ANSWER :
D. step up or step down AC voltage
15.
Galvanometer can be converted into a voltmeter by using
A.
a low resistance in series
B.
a high resistance in series
C.
A low resistance in parallel
D.
A high resistance in parallel
ANSWER :
B. a high resistance in series
16.
When two resistors, each of value 10 ohms, are connected in parallel, what is the effective value of the combination?
A.
4 ohms
B.
5 ohms
C.
6 ohms
D.
7 ohms
ANSWER :
B. 5 ohms
17.
Which one of the following common devices works on the basis of the principle of mutual induction?
A.
LED
B.
Transformer
C.
Photodiode
D.
Tube light
ANSWER :
B. Transformer
18.
The electric device with thermostat is
A.
radio
B.
electric bulb
C.
fan
D.
iron box
ANSWER :
D. iron box