Question

If the emitter current is changed by $4\text{mA}$, the collector current changes by $3.5\text{mA}$, the value of $\beta$ will be -

• A. $7$
• B. $0.875$
• C. $0.5$
• D. $3.5$

Answer 1

The correct option is A $7$

Given,
$\Delta I_E=4\text{mA}$
$\Delta I_C=3.5\text{mA}$

We know that, $\alpha =\frac{\Delta I_C}{\Delta I_E}$

$\Rightarrow \alpha =\frac{3.5}{4}=\frac{7}{8}$

Also, $\beta =\frac{\alpha }{1-\alpha }$

$\Rightarrow \beta =\frac{7/8}{1-7/8}$

$\Rightarrow \beta$ $=$ $7$