Discussion Forum

In a transistor  circuit, the collector current is changed by 8.9 mA, if the emitter  current is changed to 9.0 mA . The value of current amplification  factor $\beta$ is 

Answer:

Explanation:

As,  change in the collector  current

$\triangle I_{c}$ =8.9 mA and change in emitter  current,

$\triangle I_{E}$ =9 mA

 So, the current amplification factor, 

$\beta=\frac{\triangle I_{c}}{\triangle I_{B}}=\frac{\triangle I_{c}}{\triangle I_{E}-\triangle I_{c}}$

                                    $(\because  \triangle I_{E}=\triangle I_{c}+\triangle I_{B})$

$\Rightarrow$      $\beta=\frac{8.9}{(9-8.9)}=\frac{8.9}{0.1}=89$

 Hence, the correct option is (a)