JEE Main 2021PhysicsLaws Of MotionNewtons Laws Of MotioneasyNumerical

JEE Main 2021Laws Of Motion Question with Solution

From: JEE Main 2021 (Online) 16th March Evening Shift

Question

A body of mass 2 kg moves under a force of N. It starts from rest and was at the origin initially. After 4s, its new coordinates are (8, b, 20). The value of b is _____________. (Round off to the Nearest Integer)

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Show full solutionCorrect answer: 12
Correct answer
12

Step-by-step explanation



time = 4 sec

As body start from rest therefore
position vector initially &
u (initial velocity) = 0

given,

Now, from second equation of motion









The value of b = 12

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About this question

This is a previous-year question from JEE Main 2021, 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.