Current amplification factor of a common base configuration is `0.88`. Find the value of base current when the emitter current is `1 m A`.

Explanation

In a common-base arrangement, the current amplification factor `alpha =((Delta I_(C))/(Delta I_(E)))_(V_(CB)) = (I_(C))/(I_(E))`
Given `alpha = 0.88, I_(E) = 1 mA`
`:.` Collector current
`I_(C) = alpha I_(E) = 0.88 xx 1 = 0.88 mA`
Now since `I_(E)=I_(B) + I_(C)`
`:.` Base current `I_(B) =I_(E) -I_(C) = 1 - 0.88 = 0.12 mA`.