JEE Main 2024 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 31 January 2024, Shift 2, Physics Q41

Question 41 of 90 in this shift, Physics question 11 of 30, Section A.

By what percentage will the illumination of the lamp decrease if the current drops by 20%?

(1)36%Official answer
(2)46%
(3)56%
(4)26%

Official answer

Option 1

NTA final key.

Chapter: Current Electricity
Topic: Ohm's Law and Resistance
Idea tested: Joule Heating and Power

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Asked 5× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.