The input resistance of a silicon transistor is 100 W. Base current is changed by 40 µA which results in a change in collector current by 2mA. This transistor is used as a common emitter amplifier with a load resistance of 4 KΩ. The voltage gain of the amplifier is:

Options

(a) 2000
(b) 3000
(c) 4000
(d) 1000

Correct Answer:

2000

Explanation:

Voltage gain (Aᵥ) = Vₒᵤₜ / Vᵢₙ = Iₒᵤₜ / Iᵢₙ x Rₒᵤₜ / Rᵢₙ
Aᵥ = (2 x 10⁻³ / 40 x 10⁻⁶) x (4 x 10³ / 100)
= 2 x 100 = 2000