Question

A uniform metallic spherical shell of inner radius R has a thickness t, such that $\frac{R}{t}=1000$. The shell is kept in vacuum and also, there is vacuum inside the shell. If absolute temperature of metallic spherical shell is doubled, then the ration of new radius to new thickness $\frac{R^{\prime }}{t^{\prime }}$ will be

• A. 2000
• B. 500
• C. 1000
• D. $\sqrt{2000}$

Answer 1

The correct option is C 1000

$\frac{R^{\prime }}{t^{\prime }}=\frac{R(1+\alpha \Delta \theta )}{t(1+\alpha \Delta \theta )}=1000$. Hence the ration $\frac{t}{R}$ will remain constant on heating.