Question

A transistor has $\alpha =$ $0.95$. If the emitter current is $10mA$, the base current will be

• A. $0.1mA$
• B. $0.2mA$
• C. $0.3mA$
• D. $0.5mA$

Answer 1

The correct option is D $0.5mA$

Given that:
$\alpha =0.95$
Emitter current, $I_e=10mA$

We have:

$\alpha =\frac{I_c}{I_e}$

$I_c=\alpha \times I_e$

$I_c=0.95\times 10=9.5mA$

Also,

$I_e=I_b+I_c$

$10=I_b+9.5$

$I_b=0.5mA$