Question

Accuracy of potentiometer can be increased by
A. Increasing resistance of wire.
B. Decreasing resistance of wire.
C. Increasing the length of wire.
D. Decreasing the length of wire

Answer 1

Hint: Potentiometer works on the same principle as the Wheatstone bridge.
The potentiometer is said to be a three-terminal device.
It is most commonly used for speed control and volume control. Considering these points while answering the given question.

Complete answer:
The potentiometer is formed by semi-circle or rotary formats. We can adjust the resistance value from minimum value to maximum value.
It has three terminals; the center terminal of the rheostat serves as the wiper which helps to sweep the all resistance range. The other two terminals are fixed which is used to represent the minimum and the maximum value. It acts as a variable resistor or rheostat.
This potentiometer also acts as a voltage divider when we rotate or vary the center shaft which is connected to the wiper.
There are kinds of potentiometers available such as low-power potentiometer, linear taper potentiometer, digital potentiometer, etc... Based on the applications we can use the various kinds of potentiometers.
When we increase the wires' series resistance, then the potential gradient of the wire gets decreased which is used to measure the emf more accurately.
We can also measure the emf more accurately when we increase the length of the wire, when we increase the length of the wire the potential gradient of the wire decrease hence
we can measure the emf more accurately.

Therefore, the correct answer is an option (C). Increasing the length of the wire helps to increase the accuracy of the potentiometer.

Note:
The potentiometer can also be used as a position vector for feedback motion control.
This is also used in vacuum cleaners.
It is very useful to check the accuracy of voltmeter, ammeter, and wattmeter in engineering.