Question

The rheostat differs from a potentiometer in the respect that it;
A.) Has lower wattage rating
B.) Has a large wattage rating
C.) Has a large number of turns
D.) Offers a large number of tappings

Answer 1

Hint: A rheostat and a potentiometer are both used to change the resistance in a circuit. The potentiometer is used in electrical appliances like the transducers we use in television and joystick etc.. where small power consumption is required. While the rheostat is used in power-consuming types of machinery.

Complete step by step answer:

A potentiometer is a three-terminal device, which is used to vary the voltage that is flowing through the circuit by varying the position of the wiper. Potentiometers have low power and are most commonly used for audio devices to control television brightness, contrast, and colour, and as position transducers in joysticks and other such mechanisms.

A rheostat is a two-terminal device that is used to vary the current flowing through the circuit. The rheostats have a high power rating and are commonly used in ceiling fans, television and many other types of machinery.

So the major difference between the rheostat and the potentiometer is that the rheostat has a higher wattage rating as compared to the potentiometer.
So the answer to the question is option (A)- Has higher wattage rating.

Note: Some other differences between the rheostat and the potentiometer are,
1. A potentiometer is mainly constructed using graphite while a rheostat is made up of metal ribbon or carbon disks etc.
2. A potentiometer is usually connected parallel to a circuit while a rheostat is connected in series to a circuit.
3. A potentiometer can be used as a rheostat, while the rheostat cannot function as a potentiometer.