JEE Main 2020PhysicsLaws of MotionMediumMCQ

JEE Main 2020Laws of Motion Question with Solution

JEE Main 2020 (05 Sep Shift 2)

Question

A spaceship in space sweeps stationary interplanetary dust. As a result, its mass increases at a rate dM(t)dt=bv2(t), where v(t) is its instantaneous velocity. The instantaneous acceleration of the satellite is:

Choose an option

Show full solutionCorrect option: B
Correct answer
B-bv3M(t)

Step-by-step explanation

dM(t)dt=-bv2
in free space no external force so there in only thrust force on rocket
fin =dMdtVrel
Ma=-bv2(t)v
a=-bv3M(t)

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About this question

This is a previous-year question from JEE Main 2020, covering the Laws of Motion 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.