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Current Electricity

JEE Main level, numerical answer, medium

244 of 380

Question 244 of 380

A steel rod with $y=2.0\times {10}^{11}N{m}^{-2}$ and $\alpha ={10}^{-5}{C^{\circ}}^{-1}$ of length $4m$ and area of cross-section $10{cm}^{2}$ is heated from $0^{\circ}C$ to $400^{\circ}C$ without being allowed to extend. The tension produced in the rod is $x\times {10}^{5}N$ where the value of $x$ is $_________.$

Show answer and solution

Answer: 8

Thermal force

F=Ay\alpha \Delta T

F=\left(10\times {10}^{-4}\right)\times \left(2\times {10}^{11}\right)\left({10}^{-5}\right)(400)

F=8\times {10}^{5}N

\Rightarrow x=8

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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