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A common-emitter amplifier has a current gain of 62. Its collector resistance is 5 kΩ and its input resistance is 500 Ω. If the applied input voltage is 0.01 V, what is the output voltage?

0.62 V
6.2 V
62 V
620 V

Correct answer: 6.2 V

Solution

Voltage gain Av = beta*Rc/Ri = 62*5000/500 = 620. Output voltage = Av*Vin = 620*0.01 = 6.2 V.

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