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An automobile of mass m accelerates starting from the origin and initially at rest, while the engine supplies constant power P. The position is given…

JEE Main 2021 — Physics Mechanics

2021mcqhard

An automobile of mass mmm accelerates starting from the origin and initially at rest, while the engine supplies constant power PPP. The position is given as a function of time by:

Official previous-year question

Held on 27 Jul 2021 · Verified 6 Jul 2026.

Options

  1. A

    (9P8m)12t32{(\frac{9P}{8m})}^{\frac{1}{2}}{t}^{\frac{3}{2}}(8m9P​)21​t23​

  2. B

    (8P9m)12t23{(\frac{8P}{9m})}^{\frac{1}{2}}{t}^{\frac{2}{3}}(9m8P​)21​t32​

  3. C

    (9m8P)12t32{(\frac{9m}{8P})}^{\frac{1}{2}}{t}^{\frac{3}{2}}(8P9m​)21​t23​

  4. D

    (8P9m)12t32{(\frac{8P}{9m})}^{\frac{1}{2}}{t}^{\frac{3}{2}}(9m8P​)21​t23​

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