Question

A simple slide wire potentiometer is used for measurement of current in the circuit. The voltage drop across a standard resistor of 0.5 $\Omega$ is balanced at 100 cm. The magnitude of current of the standard cell of 2.5 V is balanced at 50 cm is ______ A.

• A. 0.1 A
• B. 1 A
• C. 10 A
• D. 100 A

Answer 1

The correct option is C 10 A

Voltage drop per unit length
$=\frac{2.5}{50}=0.05V/cm$

Voltage drop across 100 cm of length
$=0.05V/cm\times 100cm=5V$

Current through circuit,
$I=\frac{5}{0.5}=10A$