M=∫ρ4πr2dr
=∫0Rr2K4πr2dr
=4πKR
Satellite velocity =RGM=4πK
Time period, T=v2πR=4πK2πR
Now,
RT=4πK2π= constant
JEE Main 2019 — Physics Mechanics
A test particle is moving in a circular orbit in the gravitational field produced by a mass density ρ(r)=r2K. Identify the current relation between the radius R of the particle’s orbit and its period T:
Held on 9 Apr 2019 · Verified 6 Jul 2026.
TR is a constant
R3T2 is a constant
RT is a constant
R2T is a constant
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