Q. A metal rod of Young’s modulus $\gamma$ and coefficient of thermal expansion $\alpha$ is held at its two ends such that its length remains invariant. If its temperature is raised by $t℃$, the linear stress developed in it is
A) $\frac{\alpha t}{\gamma}$
B) $\frac{\gamma}{\alpha E}$
C) $\gamma\alpha t$
D) $\frac{I}{\gamma\alpha t}$
Explanation
(c) Linear expansion
$\mathrm{\Delta}L = \ \alpha V\mathrm{\Delta}T = \frac{FL}{AY}$
Stress $= \ \frac{F}{A}\ = \ \gamma\alpha\mathrm{\Delta}T$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.