Question

A meter bridge setup is shown in the figure. It is used to determine an unknown resistance R using a given resistor of 15 Ω. The galvanometer (G) shows null deflection when tapping key is at 43 cm mark from end A. If the end correction for end A is 2 cm, then the determined value of R will be ___ Ω.

Fig. Meter Bridge

Answer 1

The correct answer is 19
Using the conditions of a balanced wheat stone bridge and adding the end correction
⇒ $\frac{43+2}{15} = \frac{57}{R}$
$R = \frac{57 × 15}{45}$
$= 19Ω$