Question

State whether the given statement is True or False.
The wire of the potentiometer is made up of Aluminium.

Answer 1

Potentiometer is an electrical instrument which consists of a long piece of wire across which a battery is connected. We have to understand the nature of the instrument and its necessity of the required wire here. Application of potentiometer, requires wires which are more conductive with less resistivity or constant resistivity.

Complete answer:
Potentiometer is an electrical instrument which is used to determine the internal resistance of a cell and also for the comparison of the emfs of two cells connected with it.In a potentiometer, there is inclusion of a battery, a long wire which is cut into equal pieces joined by metallic strip and a key.For its application, the wire which is used must have a constant resistivity which must not fluctuate with ranging temperature.

Hence, the temperature coefficient of the material of the wire must be low.Aluminium is less conductive than copper and has a higher resistivity. Also, the resistivity of copper fluctuates and does not remain constant throughout every temperature.The temperature coefficient of aluminium is more than copper and others.So, as copper is not that much costly with respect to silver it is used as a wire in potentiometer.

Therefore, the statement that the wire of the potentiometer is made up of Aluminium is False.

Note: It must be noted that resistivity of a substance is defined as the resistance of the conductor of a unit cross-sectional area of unit length. Temperature coefficient refers to the change in resistance of a substance when its temperature is altered.