Question

In a common emitter amplifier, using output resistance of 5000Ω and input resistance of 2000Ω, if the peak value of input signal voltage is 10 mV and β = 50 then what is the peak value of output voltage?

(A) 2.5 × 10^–4 Volt

(B) 5 × 10^–6 Volt

(C) 1.25 Volt

(D) 125 Volt

Answer 1

The correct option is (C) 1.25 Volt.

Explanation:

For CE amplifier, 

Voltage gain = A = B ∙ (R_o / R_i)

∴        A = 50 × [(5000) / (2000)]

          A = 125

          A = [(output voltage) / (input voltage)]

∴        V_o = A ∙ V_in = 125 × 10 mV = 1250 m

          V_o = 1.25 V.