Question

Which of these is incorrect for an operational amplifier?

(a) It has a high voltage gain

(b) It is a direct coupled amplifier

(c) It is only useful for amplifying AC signals

(d) It was originally designed to perform mathematical operations

This question was posed to me in an interview for internship.

I'd like to ask this question from Operational Amplifiers topic in portion Op-amps and its Applications of Analog Circuits

Answer 1

The correct option is (c) It is only useful for amplifying AC signals

For explanation: Operational amplifier is a high voltage gain, direct coupled amplifier which can be used to perform mathematical operations on analog signals. It can be used to amplify both DC and AC signals.