Expansion of Solids
Three types of expansion-takes place in solid.
Linear Expansion Expansion in length on heating is called linear expansion. Increase in length
l2 = l1( 1 + α Δt)
where, ll and l2 are initial and final lengths, Δt = change in temperature and α = coefficient of linear expansion.
Coefficient of linear expansion α =( Δl / l * Δt)
where 1 = real length and Δl = change in length and Δt = change in temperature.
Superficial Expansion Expansion in area on heating is called superficial expansion. Increase in area A2 = A1( 1 + β Δt)
where, A1 and A2 are initial and final areas and β is a coefficient of superficial expansion.
Coefficient of superficial expansion β =( ΔA / A * Δt) where. A = area, AA = change in area and At = change in temperature.
Cubical Expansion Expansion in volume on heating is called cubical expansion. Increase in volume V2 = V1( 1 + γΔt)
where V1 and V2 are initial and final volumes and γ is a coefficient of cubical expansion.
Coefficient of cubical expansion
where V = real volume, AV = change in volume and Δt = change in temperature. Relation between coefficients of linear, superficial and cubical expansions