JEE Main 2021PhysicsOscillationsHardMCQ

JEE Main 2021 — Oscillations Question with Solution

JEE Main 2021 (26 Feb Shift 1)

Question

Assume that a tunnel is dug along a chord of the earth, at a perpendicular distance R2 from the earth's centre, where R is the radius of the earth. The wall of the tunnel is frictionless. If a particle is released in this tunnel, it will execute a simple harmonic motion with a time period:

Choose an option

Show full solutionCorrect option: B
Correct answer
B2πRg

Step-by-step explanation

Force along the tunnel

F=-GMmrR3cosθ

F=-gmRx  GMR2=g, rcosθ=x

a=-gRx

ω2=gR

T=2πRg

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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.