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A transistor operating in common-emitter configuration has a current gain of 10. If its input resistance is 20 kΩ and the load resistance is 100 kΩ, what is the power gain?
- 300
- 500
- 200
- 100
Correct answer: 500
Solution
Power gain = current gain^2 * (R_load / R_in) = 10^2 * (100k / 20k) = 100 * 5 = 500.
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