Question

Identify the relationship between base current amplification (α) and emitter current amplification (β).

(a) β=\(\frac {\alpha }{1- \alpha}\)

(b) β=\(\frac {1 – \alpha }{\alpha}\)

(c) β=\(\frac {\alpha }{1 + \alpha}\)

(d) β=\(\frac {1 + \alpha }{1 – \alpha}\)

I had been asked this question in examination.

The doubt is from Semiconductor Electronics in chapter Semiconductor Electronics : Materials, Devices and Simple Circuits of Physics – Class 12

Answer 1

The correct choice is (a) β=\(\frac {\alpha }{1- \alpha}\)

To explain: IE=IB+IC

\(\frac {I_E}{I_C} =\frac {I_B}{I_C}\) + 1

\(\frac {1}{\alpha }=\frac {1}{\beta }\) + 1

α = \(\frac {\beta }{1 + \beta}\)

Therefore, β=\(\frac {\alpha }{1- \alpha}\)