Question

What is the primary function of an operational amplifier?

• A. To decrease signal power
• B. To increase signal power
• C. To convert AC to DC
• D. To generate digital signals

Hint:

Op-Amps make weak signals strong — that’s why we call them “amplifiers”!

Answer 1

The Correct Option is B

An operational amplifier (Op-Amp) is a high-gain electronic voltage amplifier with differential inputs. Its primary function in analog circuits is to increase the power, voltage, or current of an input signal, making weak signals strong enough to be processed or transmitted.
It is most commonly used in configurations like voltage followers, inverting and non-inverting amplifiers, integrators, differentiators, and active filters.
Clarifying the incorrect options:

• (A) Decreasing signal power is not a typical function of Op-Amps — attenuation is a different operation.
• (C) Converting AC to DC is done by rectifiers, not amplifiers.
• (D) Op-Amps deal with analog signals, not digital signal generation.

Thus, the fundamental role of an Op-Amp is to increase signal power by amplification.