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Concepts Of Physics MCQ Edition [Volume 2]PhysicsSemiconductors and Semiconductor Devices

An amplifier circuit employs a transistor in common-emitter mode, with a load resistor of 2 k connected in the collector branch. The transistor has a current gain = 50 and an input resistance of 0.50 k . When the input current is altered by 50 A , what is the power gain of the amplifier?

Options

  1. A200
  2. B2500
  3. C500
  4. D10^4

Correct answer

D. 10^4

Step-by-step solution

The power gain of a common-emitter amplifier is given by the product of the square of the current gain and the resistance ratio. Power gain A_p = ^2 R_L R_ in Given values are: Current gain = 50 Output resistance R_L = 2 k Input resistance R_ in = 0.50 k Substituting the values into the formula: A_p = (50)^2 2 0.50 A_p = 2500 4 = 10000 = 10^4 The change in input current is extra information and is not required to find the power gain.

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