Ncert Exercises & Solutions

The radius of a metal sphere at room temperature T is R and the coefficient of linear expansion of the metal is $α$ . The sphere heated a little by a temperature $∆$ T so that its new temperature is T+ $∆$ T. The increase in the volume of the sphere is approximately:

1. $2 πRα ∆ T$

2. ${πR}^{2} α ∆ T$