Question
Explain the concept of rheostat.
✓
Answer
- A rheostat is an adjustable resistor used in applications that require adjustment of current or resistance in an electric circuit.
- The rheostat can be used to adjust potential difference between two points in a circuit, change the intensity of lights and control the speed of motors, etc.
- Its resistive element can be a metal wire or a ribbon, carbon films or a conducting liquid, depending upon the application.
- In hi-fi equipment, rheostats are used for volume control.
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