JEE Main 2012 — Current Electricity Question with Solution
JEE Main 2012 (26 May Online)
Question
In an experiment of potentiometer for measuring the internal resistance of primary cell a balancing length is obtained on the potentiometer wire when the cell is open circuit. Now the cell is short circuited by a resistance . If is to be equal to the internal resistance of the cell the balancing length on the potentiometer wire will be
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Show full solutionCorrect option: C
Correct answer
C
Step-by-step explanation
Balancing length will give emf of cell
Here is potential gradient.
If the cell is short circuited by resistance 'R'
Let balancing length obtained be then
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This is a previous-year question from JEE Main 2012, 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.