JEE Main 2021PhysicsMechanical Properties of SolidsMediumMCQ

JEE Main 2021 — Mechanical Properties of Solids Question with Solution

JEE Main 2021 (26 Aug Shift 2)

Question

Two blocks of masses 3 kg and 5 kg are connected by a metal wire going over a smooth pulley. The breaking stress of the metal is 24π×102 N m-2. What is the minimum radius of the wire ?
( take g=10 m s-2

Choose an option

Show full solutionCorrect option: D
Correct answer
D12.5 cm

Step-by-step explanation

Tension in the string =2m1m2m1+m2g

=2×3×5×108=752

Stress =TA

24π×102=752πr2

r2=7548×10-2

r2=0.015625

r=0.125 m=12.5 cm

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Mechanical Properties of Solids chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2021, covering the Mechanical Properties of Solids 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.