Question

The base current in a transistor circuit changes from $45\mu A$ to $140\mu A$. Accordingly, the collector current changes from $0.2mA$ to $4.00mA$. The gain in current is:

• A. $9.5$
• B. $1$
• C. $40$
• D. $20$

Answer 1

Answer: (C)

$40$

Current gain of transistor is defined as

$g_I=\frac{\Delta I_C}{\Delta I_B}$.

Hence, in this case,

$g_I=\frac{4mA-0.2mA}{140\mu A-45\mu A}=\frac{3800}{95}=40$