JEE Main 2021PhysicsOscillationsMediumMCQ

JEE Main 2021 — Oscillations Question with Solution

JEE Main 2021 (31 Aug Shift 2)

Question

A bob of mass m suspended by a thread of length ℓ undergoes simple harmonic oscillations with time period T. If the bob is immersed in a liquid that has density 14 times that of the bob and the length of the thread is increased by 13rd of the original length, then the time period of the simple harmonic oscillations will be:

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Show full solutionCorrect option: B
Correct answer
B43T

Step-by-step explanation

T=2πℓg
geff=g-g4=3g4  ∴ T'=2π4ℓ/33g/4=2π16ℓ9g
T'=43 T

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About this question

This is a previous-year question from JEE Main 2021, covering the Oscillations 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.