Question:easy
In common emitter mode of transistor, the d.c. current gain is 20, the emitter current is 7 mA. The collector current is
In common emitter mode of transistor, the d.c. current gain is 20, the emitter current is 7 mA. The collector current is
Show Hint
The emitter current is the sum of the base and collector currents, and the dc current gain beta is Ic over Ib.
Updated On: Oct 1, 2026
- \(\frac{20}{3}\) mA
- \(\frac{14}{5}\) mA
- \(\frac{1}{3}\) mA
- \(\frac{8}{13}\) mA
Show Solution
The Correct Option is A
Solution and Explanation
Step 1: Use alpha.
$\alpha = \dfrac{\beta}{1 + \beta} = \dfrac{20}{21}$ and $\alpha = \dfrac{I_C}{I_E}$.
Step 2: Calculate.
$I_C = \alpha I_E = \dfrac{20}{21}\times 7 = \dfrac{20}{3}$ mA.
Final Answer:
Option (A). \[ \boxed{\frac{20}{3}\text{ mA}} \]
$\alpha = \dfrac{\beta}{1 + \beta} = \dfrac{20}{21}$ and $\alpha = \dfrac{I_C}{I_E}$.
Step 2: Calculate.
$I_C = \alpha I_E = \dfrac{20}{21}\times 7 = \dfrac{20}{3}$ mA.
Final Answer:
Option (A). \[ \boxed{\frac{20}{3}\text{ mA}} \]
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