Question

What is Balancing Length In Potentiometer?

Answer 1

When the potentiometer is understood, the working of the potentiometer may explain. It's a three-terminal resistor with either sliding or rotating contacts that acts as a voltage divider that can be adjusted. The potentiometer should only have two terminals, one end, and the wiper if it is used as a rheostat or variable resistor.

Complete step-by-step solution:
The jockey refers to the balancing length as the balance length wire in a potentiometer. The internal resistance is proportional to the balancing length of the potentiometer and the emf of the battery.
A potentiometer is made up of a long wire composed of manganin or constantan with a uniform cross-section area.
The potential drop per unit length is known as the potential gradient $\left( K \right)$ . It's calculated as $\dfrac{V}{L}$ , with $V$ denoting the potential difference between two points and L denoting the distance between them. In addition,$K{\text{ }} = \dfrac{{\left( {\dfrac{{IL}}{A}} \right)}}{L} = {\text{ }}\dfrac{I}{A}$.
The equation $\dfrac{{{E_1}}}{{{E_2}}}\; = {\text{ }}\dfrac{{{L_1}}}{{{L_2}}}$ compares the emf of two cells, where ${E_1}$ and ${E_2}$are the emf and ${L_1}$ and ${L_2}$ are the lengths at which they are balanced.
The formula for calculating the cell's internal resistance is $r{\text{ }} = {\text{ }}R\dfrac{{\left( {{L_1}{\text{ }} - {\text{ }}{L_2}} \right)}}{{{L_2}}}$.

Note:
In a circuit, a potentiometer is used to measure the potential difference. It can also be used to calculate a cell's emf and compare two cells' EMFs. A potentiometer can also be used to calculate the cell's internal resistance.
A voltmeter draws a little amount of current from the circuit's voltage source, therefore the reading displayed on the voltmeter may not be correct.
The potentiometer draws no current from the circuit and provides a precise reading.
A potentiometer is made up of a long wire composed of manganin or constantan with a uniform cross-section area.