JEE Main 2020 · PhysicsNumerical answerNumerical valueMediumMulti-step

JEE Main 9 January 2020, Shift 1, Physics Q23

Question 23 of 75 in this shift, Physics question 23 of 25, Section B.

A body of mass m=10 kg is attached to one end of a wire of length 0.3 m. The maximum angular speed (in rad

\mathrm{s^{-1}}

) with which it can be rotated about its other end in space station is (Breaking stress of wire=

4.8\times10^{7}\ \mathrm{Nm^{-2}}

and area of cross-section of the wire=

10^{-2}\ \mathrm{cm^{2}}

) is :

Official answer

4.00

NTA final key (Jan 2020).

Chapter: Mechanical Properties of Solids
Topic: Elasticity
Idea tested: Breaking Stress and Breaking Force

Same idea in other shifts

Asked 7× in all

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29 Jul 2022, Shift 2 · Q53A metal wire of length 0.5 m and cross-sectional area $10^{-4}\ \mathrm{m^2}$ has breaking stress $5\times10^8\ \mathrm{Nm^{-2}}$ . A block…MediumNumerical value
26 Aug 2021, Shift 2 · Q13Two 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…MediumDiagram basedHas a figure
27 Aug 2021, Shift 2 · Q24Wires $W_1$ and $W_2$ are made of same material having the breaking stress of $1.25\times10^9\ \mathrm{N/m^2}$ . $W_1$ and $W_2$ have…MediumNumerical valueHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.