In an n-p-n transistor, the current gain for common emitter configuration is 80. If the emitter current be 8.1 mA, then the base current will be

Options

A. 0.1 `mu A`
B. `0.01 muA`
C. `0.1 muA`
D. `0.01 mA`

Answer

C

Explanation

`beta=800, I_(e)=8.1 mA, I_(b)= ? `
`beta=(I_(c))/(I_(b))=(I_(e)-I_(b))/(I_(b))`
`betaI_(b)=I_(e)-I_(b)`
`I_(b)=(I_(e))/(beta+1)=(8.1)/(81)=0.1 mA`