JEE Main 2021 — Current Electricity Question with Solution
From: JEE Main 2021 (Online) 25th July Morning Shift
Question
An electric bulb rated as 200 W at 100 V is used in a circuit having 200 V supply. The resistance 'R' that must be put in series with the bulb so that the bulb delivers the same power is _____________ .
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Show full solutionCorrect answer: 50
Correct answer
50
Step-by-step explanation
Power,
To produce same power, same voltage (i.e. 100 V) should be across the bulb.
Hence, R = RB
R = 50
To produce same power, same voltage (i.e. 100 V) should be across the bulb.
Hence, R = RB
R = 50
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This is a previous-year question from JEE Main 2021, 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.