Net change in length =0
Thermal expansion. Δl=lαΔt
Y=lΔlAF
lΔl=AYF
Δl=AYFl
AYFl=lαΔt
F=AYαΔt
JEE Main 2017 — Physics Thermodynamics
A compressive force, F is applied at the two ends of a long thin steel rod. It is heated, simultaneously, such that its temperature increases by ΔT. The net change in its length is zero. Let l be the length of the rod, A its area of cross-section, Y its Young's modulus, and α its coefficient of linear expansion. Then, F is equal to:
Held on 8 Apr 2017 · Verified 6 Jul 2026.
lAYαΔT
AYαΔT
αΔTAY
l2YαΔT
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Work through every JEE Main Thermodynamics PYQ, year by year.