JEE Main 2021PhysicsMechanical Properties of SolidsEasyNumerical

JEE Main 2021 — Mechanical Properties of Solids Question with Solution

JEE Main 2021 (22 Jul Shift 1)

Question

The area of cross-section of a railway track is 0.01 m2. The temperature variation is 10 °C. Coefficient of linear expansion of material of track is 10-5 C-1∘. The energy stored per meter in the track is J m-1. (Young's modulus of material of track is 1011 N m-2)

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Show full solutionCorrect answer: 5
Correct answer
5

Step-by-step explanation

Elastic energy =Y2(strain)2× Area × length

⇒ Elastic energy per unit length =Y2(strain)2× Area

(strain =Δℓℓ=αΔT=10-5×10=10-4)
=10112×10-42×10-2=5 J m-1

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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.