In a P N P transistor working as a common-base amplifier, current gain is 0.96 and emitter current is 7.2 mA. The base current is

Question

In a P N P transistor working as a common-base amplifier, current gain is 0.96 and emitter current is 7.2 mA. The base current is (A) 0.4 mA (B) 0.2 mA (C) 0.29 mA (D) 0.35 mA

Tardigrade Admin · Accepted Answer

α=(ic/ie)=0.96 and ie=7.2 mA ic=0.96 × ie=0.96 × 7.2=6.91 mA ∴ ie=ic+ib ⇒ 7.2=6.91+ib ⇒ ib=0.29 mA

Q. In a $PNP$ transistor working as a common-base amplifier, current gain is $0.96$ and emitter current is $7.2 m A$ . The base current is

0.4 mA

0.2 mA

0.29 mA

0.35 mA

$α = \frac{i _{c}}{i _{e}} = 0.96$ and $i_{e} = 7.2 m A$
$i_{c} = 0.96 \times i_{e} = 0.96 \times 7.2 = 6.91 m A$
$∴ i_{e} = i_{c} + i_{b}$
$\Rightarrow 7.2 = 6.91 + i_{b}$
$\Rightarrow i_{b} = 0.29 m A$

Q. In a PNP transistor working as a common-base amplifier, current gain is 0.96 and emitter current is 7.2mA. The base current is