Question

Two amplifiers are connected one after the other in series (cascaded).The first amplifier has a voltage gain of 10 and the second has avoltage gain of 20. If the input signal is 0.01 volt, calculate the outputac signal.

Answer 1

It is given that the voltage gain of the first amplifier, A 1 =10 and the voltage gain of second amplifier, A 2 =20 and the input signal voltage, V i =0⋅01 V.

The formula of total voltage gain if amplifiers are connected in series is,

A= A 1 × A 2

Substitute the values in above expression.

A=10×20 A=200

The formula of voltage amplification is,

A= V 0 V i

Substitute the values in above expression.

200= V 0 0⋅01 V 0 =2 V

Hence, the voltage of output signal is 2 V.