SAQ : Define the coefficient of linear expansion of a solid. Give its mathematical expression. Mention its units.

Question

Define the coefficient of linear expansion of a solid. Give its mathematical expression. Mention its units.

Answer

Coefficient of linear expansion: The coefficient of linear expansion of a solid is the increase in its length per unit length per degree rise of temperature.

The mathematical expression of the coefficient of linear expansion:

α=l_2−l_1\over l_1(t_2−t_1)

l₁ = Initial length

l₂ = Final length

t₁ = Initial Temperature

t₂ = Final Temperature

Unit of the coefficient of linear expansion:

It is expressed as per degree Celcius (^oC^-1) or per degree kelvin (K^-1)