JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 26 August 2021, Shift 2, Physics Q3

Question 3 of 90 in this shift, Physics question 3 of 30, Section A.

If the length of the pendulum in pendulum clock increases by 0.1%, then the error in time per day is :

(1)86.4 s
(2)8.64 s
(3)43.2 sOfficial answer
(4)4.32 s

Official answer

Option 3

NTA final key.

Chapter: Oscillations
Topic: Pendulums
Idea tested: Thermal Expansion Effects on Clocks

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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 108 of the 174 JEE Main shifts held from 2017 to 2026.