When heat is supplied to material, its dimensions(length, area, volume) can be changed due to change in its temperature.The phenomenon of change in dimensions of an object due to heat supplied is known as thermal expansion.
Types Of Thermal Expansion
There are three types of thermal expansion.(I) Linear Expansion(II) Area Expansion(III) Volume Expansion
(I) Linear Expansion
The extension in length of a body due to increase in its temperature is called the linear expansion.If a rod having initial length l₁ at temperature T₁ and final increased length l₂ at temperature T₂, then
(II) Area Expansion
The expansion in area of a surface due to increase in its temperature is called area expansion.
If a plate having initial area A₁ at temperature T₁ and final area A₂ at temperature T₂, then
(III) Volume Expansion
The expansion in volume of an object due to increase in its temperature is known as volume expansion.
If a plate having initial volume V₁ at temperature T₁ and final volume V₂ at temperature T₂, then