Electronics and Communication Engineering - Analog Electronics

1.
A full wave rectifier circuit using centre tapped transformer and a bridge rectifier are fed at 100 V, 50 Hz. The frequencies of outputs in these two rectifiers are
100 Hz each
50 Hz each
100 Hz and 50 Hz
50 Hz and 100 Hz
Answer: Option
Explanation:

Output wave in each case has two cycles for one cycle of input wave.


2.
When the ac base voltage in a CE amplifier circuit is too high, the ac emitter current is
zero
constant
alternating
distorted
Answer: Option
Explanation:

A high signal causes distortion because v-i characteristics of BJT is non-linear.


3.
When load is coupled to class A amplifier through transformer, efficiency decreases.
True
False
Answer: Option
Explanation:

Transformer coupling increases efficiency.


4.
The gain of an FET amplifier can be changed by changing
rm
gm
Rd
none of the above
Answer: Option
Explanation:

Gain is proportional to gm .


5.
The open loop gain of an actual op-amp is about 100.
True
False
Answer: Option
Explanation:

It is very high.