Q. The temperature of a metallic sphere of radius R is increased by a small amount ΔT. If the linear coefficient of thermal expansion of the metal is α, the approximate increase in the volume of the sphere is:
A) $6\pi R^3\alpha\Delta T$
B) $2\pi R^3\alpha\Delta T$
C) $3\pi R^3\alpha\Delta T$
D) $4\pi R^3\alpha\Delta T$
Explanation
[Solution from source] The volume coefficient is $\gamma=3\alpha$, so $\Delta V=3\alpha\cdot\frac43\pi R^3\Delta T=4\pi R^3\alpha\Delta T$. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.