NTA Abhyas JEE Main2020PhysicsSemiconductorsPractice
A C E amplifier, has a power gain of 40   dB . The input resistance and output load resistance are 500   Ω and 2   k Ω respectively. Find the value of common-emitter current gain. [Take gain in dB = 10 log P out P in ]
Correct answer
50
Step-by-step solution
Given that, Power gain ( A P ) = 40 dB ∴ 10 l o g P 0 P i n = 40 ∴ l o g P 0 P m = 4 ∴ P 0 P in = 10 4 Also, A P = β 2 × Resistance gain = β 2 × R o u t R i n = β 2 × 2000 500 = β 2 × 4 ∴ β 2 = 10 4 4 ∴ β = 100 2 = 50