Using the conditions of a balanced wheatstone bridge and adding the end correction.
R15=(L+e)−(l+e)l+e⇒(43+2)15=(102−45)R⇒R=4557×15
⇒R=19Ω
JEE Main 2022 — Physics Electromagnetism
A meter bridge setup is shown in the figure. It is used to determine an unknown resistance R using a given resistor of 15Ω. The galvanometer (G) shows null defection when tapping key is at 43cm mark from end A. If the end correction for end A is 2cm, then the determined value of R will be Ω.

Held on 28 Jun 2022 · Verified 6 Jul 2026.
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