Question

Why do we prefer a potentiometer with a longer bridge wire?

Answer 1

Potentiometer:

• It is a 3-terminal device used to measure unknown voltage by comparing it to the known voltage.

Potentiometer Circuit

Sensitivity of a potentiometer:

• It can be defined as the smallest potential difference that a device can measure.
• This is determined by the ratio of potential (V) and the length of bridge wire (L), $Sensitivity=\frac{V}{L}$. This implies that, sensitivity is inversely proportional to the length of wire.
• So, a longer wire is used to increase the sensitivity of the potentiometer.

Hence, a longer bridge wire is so that the potentiometer is more sensitive.