JEE Main 2003 — Current Electricity Question with Solution
From: AIEEE 2003
Question
The length of a wire of a potentiometer is , and the of its standard cell is volt. It is employed to measure the of a battery whose internal resistance in If the balance point is obtained at from the positive end, the of the battery is
where is the current in the potentiometer wire.
Choose an option
Show full solutionCorrect option: D
Correct answer
D, where i is the current in the potentiometer
wire
Step-by-step explanation
Potential gradient along wire, K = volt/cm
For battery V = E' – ir, where E' is emf of battery.
or K × 30 = E' – ir, where current i is drawn from battery
or = E' + 0.5i
or E' =
For battery V = E' – ir, where E' is emf of battery.
or K × 30 = E' – ir, where current i is drawn from battery
or = E' + 0.5i
or E' =
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This is a previous-year question from JEE Main 2003, 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.