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The voltage gain of an amplifier with 9% negative feedback is 10. The voltage gain without feedback will be

1. 90
2. 10
3. 1.25
4. 100

Correct answer: 90

Solution

The voltage gain with negative feedback (Af) is related to the voltage gain without feedback (A) by the formula Af = A / (1 + βA), where β is the feedback factor. Given Af = 10 and β = 0.09, solving for A gives A = 90.

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