Two amplifiers are connected one after other in series. The first amplifier has voltage gain of 15 and second has voltage gain of 20. If input signal voltage is 0.3 V, the output signal voltage is

Introduction

NEET

100 V

105 V

90 V

9 V

Solution:

When two amplifiers are connected in series (cascaded), the total voltage gain is the product of their individual voltage gains.

Voltage gain of the first amplifier (A_v1) = 15

Voltage gain of the second amplifier (A_v2) = 20

Total voltage gain (A_v_total) = A_v1 × A_v2 = 15 × 20 = 300

Input signal voltage (V_in) = 0.3 V

The output signal voltage (V_out) is given by:

V_out = A_v_total × V_in

V_out = 300 × 0.3 V

V_out = 90 V

Thus, the output signal voltage is 90 V.