Elastic energy =2Y(strain)2× Area × length
⇒ Elastic energy per unit length =2Y(strain)2× Area
(strain =ℓΔℓ=αΔT=10−5×10=10−4)
=21011×(10−4)2×10−2=5Jm−1
The area of cross-section of a railway track is 0.01m2. The temperature variation is 10∘C. Coefficient of linear expansion of material of track is 10−5C−1∘. The energy stored per meter in the track is Jm−1. (Young's modulus of material of track is 1011Nm−2)
Held on 22 Jul 2021 · Verified 6 Jul 2026.
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