Question

A rheostat is used in an electrical circuit

• A. to change the resistance of the circuit.
• B. to change the potential difference.
• C. to change the emf.
• D. to change the current through a particular instrument.

Answer 1

The correct option is A to change the resistance of the circuit.

A rheostat is a variable resistor which is used to control current. they are able to vary the resistance in circuit without interruption. the construction of a rheostat is very similar to potentiometer .Thus A rheostat is used in circuit to change the resistance of the circuit. so option correct is A.