A transistor is operated in common-emitter configuration

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A transistor is operated in common-emitter configuration at V_c = 2 V such that a change in the base current from 100 µA to 200 µA produces a change in the collector current from 5 mA to 10 mA. The current gain is

1. 100
2. 150
3. 50
4. 75

Correct Option: C

ΔI_E = ΔI_B + ΔI_C

β =	ΔI_C
	ΔI_B

ΔI_C = (10 - 5)10^-3
= 5 × 10^-3A
ΔI_C = (200 - 100)10^-6
= 100 × 10^-6A

β =	5 × 10^-3	=	5	× 1000 = 50
	100 × 10^-6		100