JEE Main 2019PhysicsGravitationHardMCQ

JEE Main 2019 — Gravitation Question with Solution

JEE Main 2019 (09 Apr Shift 2)

Question

A test particle is moving in a circular orbit in the gravitational field produced by a mass density ρr=Kr2. Identify the current relation between the radius R of the particle’s orbit and its period T:

Choose an option

Show full solutionCorrect option: C
Correct answer
CTR is a constant

Step-by-step explanation

M=∫ρ4πr2dr
=∫0RKr24πr2dr
=4πKR
Satellite velocity =GMR=4πK
Time period, T=2πRv=2πR4πK
Now,
TR=2π4πK= constant

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About this question

This is a previous-year question from JEE Main 2019, covering the Gravitation 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.