Potentiometer & Rheostat

There are two types of variable resisters :

1. Definitions

• Potentiometer: A 3-terminal variable resistor used to vary voltage in a circuit (commonly used for voltage division).
• Rheostat: A 2-terminal variable resistor used to control current by adjusting resistance.

Potentiometer symbol

3

Rhestat symbol

2. Comparison

Feature	Potentiometer	Rheostat
Terminals	3	2
Function	Voltage control (acts as voltage divider)	Current control (adjusts resistance)
Connection	Connected across voltage source	Connected in series with load
Common Usage	Volume controls, sensor calibration	Motor speed control, light dimmers
Accuracy	More precise control	Less precise
Power Handling	Generally lower	Higher

4. Note

A potentiometer can be used as a rheostat by using only two terminals, but a rheostat cannot function as a potentiometer due to its limited terminal configuration.

5.Video Explanation

video coming soon