Three amplifiers are connected in series, (cascaded). The first amplifier has voltage gain of 5, second has voltage gain of 10 and 3^rd has voltage gain of 20. If the. Input signal is 0.1 V, then the final output of AC signal will be

100 V

We know, output voltage = (Voltage gain) (Input voltage)

Voltage gain = (Voltage gain)₁ . (Voltage gain)₂ . (Voltage gain)₃

V_out = (5) (10) (20) [0.1V]

V_out = 100 V