Q: In a common transistor circuit , the current gain is 0.98 . On changing emitter current by 5 mA , the change in collector current is

(a) 0.196 mA

(b) 2.45 mA

(c) 4.9 mA

(d) 5.1 mA

Ans:(c)

Sol: Current gain , $\large \alpha = \frac{\Delta I_c}{\Delta I_e} $

$\large 0.98 = \frac{\Delta I_c}{5} $

ΔIc = 4.9 mA