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A sand dropper drops sand of mass m(t) on a conveyer belt at a rate proportional to the square root of speed (v) of the belt, i.e. dm dt ∝ √v. If P…

JEE Main 2025 — Physics Mechanics

2025mcqhard

A sand dropper drops sand of mass m(t)m(t)m(t) on a conveyer belt at a rate proportional to the square root of speed (v)(v)(v) of the belt, i.e. dmdt∝v\frac{\mathrm{dm}}{\mathrm{dt}} \propto \sqrt{v}dtdm​∝v​. If P is the power delivered to run the belt at constant speed then which of the following relationship is true?

Official previous-year question

Held on 29 Jan 2025 · Verified 6 Jul 2026.

Options

  1. A

    P∝v\mathrm{P} \propto \sqrt{v}P∝v​

  2. B

    P∝v\mathrm{P} \propto vP∝v

  3. C

    P2∝v5\mathrm{P}^2 \propto v^5P2∝v5

  4. D

    P2∝v3\mathrm{P}^2 \propto v^3P2∝v3

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