Question

For common emitter configuration of a transistor, the collector voltage $V_c=2V$ and, base current changes from $100\mu Ato200\mu A$, and collector current changes from 5 mA to 10 mA. The current gain is

• A. 100
• B. 25
• C. 125
• D. 50

Answer 1

Answer: (D)

50

Current gain $\beta =\frac{\Delta i_c}{\Delta i_b}$
Given, $\Delta i_c=5\times {10}^{-3}A,\Delta i_b=100\times {10}^{-6}A$
$\beta =\frac{5}{100}\times 1000=50$