JEE Main 2020PhysicsLaws of MotionHardNumerical

JEE Main 2020 — Laws of Motion Question with Solution

JEE Main 2020 (07 Jan Shift 2)

Question



Consider a uniform cubical box of side a on a rough floor that is to be moved by applying minimum possible force F at a point b above its centre of mass (see figure). If the coefficient of friction is μ=0.4 , the maximum possible value of 100×ba for a box not to topple before moving is ________

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Show full solutionCorrect answer: 50
Correct answer
50

Step-by-step explanation


For no toppling
Fa2+b≤mga2
μa2+μb≤a2
0.2a+0.4b≤0.5a
0.4b≤0.3a
b≤3a2
b≤0.75a (in limiting case)
But it is not possible as b can maximum be equal to 0.5a
∴100bamax=50.00

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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.