The input resistance of a silicon transistor is `100 Omega`. Base current is changed by `40 muA` which results in a change in collector current by `2 mA`. This transistor is used as a common-emitter amplifier with a load resistance of `4k Omega`. The voltage gain of the amplifier is

Options

A. 3000
B. 4000
C. 1000
D. 2000

Answer

D

Explanation

`"Current gain "(beta)=(DeltaI_(C))/(DeltaI_(B))=(2xx10^(-3))/(40xx10^(-6))`
`beta=50`
`"Voltage gain "=beta((R_("out"))/(R_("in")))`
`=50((4xx10^(3))/(100))`
`=2000`