JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 22 July 2021, Shift 2, Physics Q25

Question 25 of 90 in this shift, Physics question 25 of 30, Section B.

The area of cross-section of a railway track is

0.01\ \mathrm{m^2}

. The temperature variation is

10^\circ

C. Coefficient of linear expansion of material of track is

10^{-5}/^\circ

C. The energy stored per meter in the track is ________ J/m. (Young’s modulus of material of track is

10^{11}\ \mathrm{Nm^{-2}}

)

Official answer

NTA final key.

Chapter: Mechanical Properties of Solids
Topic: Elasticity
Idea tested: Elastic Potential Energy

Same idea in other shifts

Asked 4× in all

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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.