A charge of 8.0 mA in the emitter current brings a charge of 7.9 mA in the collector current. The values of `alpha and beta` are

Options

A. `0.99, 90`
B. `0.96, 79 `
C. `0.97, 99`
D. `0.99, 79`

Answer

D

Explanation

Given that , change in emitter current `triangle//_(E) = 8 mA`
and change in collector current
`triangle//_(c ) = 79 mA`
We know that,
`alpha = (triangle//_(c))/(triangle//_(E)) rArr alpha = (7.9)/(8)`
`rArr alpha ~~ 0.99`
Also, we know that
`beta = (alpha)/(1-alpha) rArr beta = (7.9)/(0.1) = 79`
Hence, `alpha = 0.99 and beta = 79.`