Question

The Common Emitter amplifier has voltage gain equal to 300 and its input signal is 0.5cos(100 t) volt. The output signal will be equal to_______. 

(A) 150 cos (100t) 

(B) 300 cos (100t) 

(C) 150 cos (100t + π) 

(D) 300 cos (100t – π)

Answer 1

The correct option is (C) 150 cos (100t + π).

Explanation:

V_in = 0.5 cos 100t 

Voltage gain = β = 300 

(V_o / V_in) = gain 

Hence V_o = gain × V_in 

= 300 × (0.5 cos 100t) 

V_o = 150 cos (100 t + π) 

phase shift of π exists between input and output in CE amplifier.