Question

Consider a solid body with dimensions L1 and L2. If the surface area of this body is Ai at some initial temperature and then changes by A when the temperature changes by T. If α is the coefficient of linear expansion of this solid, prove that: A = 2 Ai T

Answer 1

Answer:

The expansion of alcohol in a thermometer is one of many commonly encountered examples of thermal expansion, the change in size or volume of a given mass with temperature. Hot air rises because its volume increases, which causes the hot air’s density to be smaller than the density of surrounding air, causing a buoyant (upward) force on the hot air. The same happens in all liquids and gases, driving natural heat transfer upwards in homes, oceans, and weather systems. Solids also undergo thermal expansion. Railroad tracks and bridges, for example, have expansion joints to allow them to freely expand and contract with temperature changes.