Question

In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2kOmega is 2V. If the base resistance is 1kOmega and the current amplification of the transistor is 100, the input signal voltage is:​

Answer 1

Explanation:

For a CE-transistor amplifier, the audio signal voltage across the collected resistance of 2 kΩ is 2 V. Suppose the current amplification factor of the transistor is 100, find the input signal voltage and base current, if the base resistance is 1 kΩ.

Answer 2

Solution: 10mV

Explanation:

Current amplification factor

β = ∆Ic / ∆Iʙ

Collector resistance

∆Ic = 2V / 2 × 10^3Ω = 1 × 10^-3 A

Base current

∆Iʙ = Vʙ / Rʙ = Vʙ / 1 × 10^-3

Given, β = 100

Now, 100 = 10^-3 / Vʙ × 10^-3

Vʙ = 1 /100 V = 10mV

∴ The input signal voltage is 10mV !