Section 10.2 Thermal Expansion
You may have observed that Jammed lid of a bottle can be easily unscrewed if it is put into the hot water for sometime. A partially inflated balloon expands to full size when placed in lukewarm water. A fully inflated balloon begins shrinking when immersed in cold water. Most materials expand on heating and contract on cooling. The physical property of a material due to which a body can change its dimensions with a change in temperature is called a thermal expansion. The expansion in length is called linear expansion, the expansion in area is called superficial expansion, and the expansion in volume is called volumetric expansion. or bulk expansion.
