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A test particle is moving in a circular orbit in the gravitational field produced by a mass density ρ (r)= K ^2. Identify the current relation…

JEE Main 2019 — Physics Mechanics

2019mcqhard

A test particle is moving in a circular orbit in the gravitational field produced by a mass density ρ(r)=Kr2.\rho (r)=\frac{K}{{r}^{2}}.ρ(r)=r2K​. Identify the current relation between the radius RRR of the particle’s orbit and its period T:T:T:

Official previous-year question

Held on 9 Apr 2019 · Verified 6 Jul 2026.

Options

  1. A

    TRTRTR is a constant

  2. B

    T2R3\frac{{T}^{2}}{{R}^{3}}R3T2​ is a constant

  3. C

    TR\frac{T}{R}RT​ is a constant

  4. D

    TR2\frac{T}{{R}^{2}}R2T​ is a constant

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