An op-amp has an open-loop gain of 105 and an openloop upper

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An op-amp has an open-loop gain of 10⁵ and an openloop upper cut off frequency of 10 Hz. If this op-amp is connected as an amplifier with a closed-loop gain of 100. Then the new upper cut off frequency is:

1. 10 Hz
2. 100 Hz
3. 10 kHz
4. 100 kHz

Correct Option: C

Given that
A_OL = 10⁵
f_H = 10 Hz
A_CL = 100

A_CL =	A_OL
	1 + A_OL · β

1 + A_OL β =	10⁵	= 10³
	100

Since due to close loop, gain reduces while uppercut off frequency increases by a factor of (1 + A_OL β)
f_{H_{^* = f_H (1 + A_OL β)
= 10 (10³)
= 10 kHz
Hence alternative (C) is the correct choice.}}