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

Explanation

In a common-base arrangement, the current amplification factor.
`alpha = ((Delta I_C)/( Delta I_E ))_(V_(CE ))=(I_C)/(I_E )`
Given `alpha = 0.88,I_E = 1mA. `
`therefore ` Collector current
`I_C = alpha I_E = 0.888 xx 1 = 0.88 mA `
Now since `l_E = I_B +I_C `
`therefore `Base current `I_B =I_E-I_C = 1 -0.88 = 0.12 mA`.