JEE Main 2023 — Current Electricity Question with Solution
From: JEE Main 2023 (Online) 29th January Evening Shift
Question
A null point is found at 200 cm in potentiometer when cell in secondary circuit is shunted by 5. When a resistance of 15 is used for shunting, null point moves to 300 cm. The internal resistance of the cell is ___________.
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Show full solutionCorrect answer: 5
Step-by-step explanation
Let the emf is E and internal resistance is r of this secondary cell so
so
&
or
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This is a previous-year question from JEE Main 2023, covering the Current Electricity chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.