Question

Consider the negative feedback system shown in the figure with \( R_o \) as output resistance of the feedback amplifier. The overall output resistance of the negative feedback amplifier is 

• A. \( R_o(1 + A \beta) \)
• B. \( R_o \left( 1 + \frac{1}{A \beta} \right) \)
• C. \( \frac{R_o}{(1 + A \beta)} \)
• D. \( R_o \times (1 + \beta) \)

Hint:

For negative feedback amplifiers, the overall output resistance decreases as the feedback factor \( \beta \) increases.

Answer 1

The Correct Option is C

- The output resistance of a negative feedback amplifier is determined by the equation \( R_o \times \frac{1}{(1 + A \beta)} \), where \( A \) is the amplifier gain and \( \beta \) is the feedback factor.
Conclusion: The correct formula for the overall output resistance of the amplifier is given by option (c).