JEE Main 2021PhysicsWork Power EnergyHardMCQ

JEE Main 2021 — Work Power Energy Question with Solution

JEE Main 2021 (27 Jul Shift 2)

Question

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 as a function of time by:

Choose an option

Show full solutionCorrect option: D
Correct answer
D8P9 m12t32

Step-by-step explanation

P=const

P=FV=mv2 dvdx

∫0xPmdx=∫0vv2 dv

Pxm=v33

3Pxm13=v=dxdt

3Pm13∫0tdt=∫0xx-13dx

⇒x=8P9 m12t32

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About this question

This is a previous-year question from JEE Main 2021, covering the Work Power Energy 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.