Most materials expand when heated. As long as the temperature change isn't too large, each dimension of an object expands according to the equation:

DL = L_oaDT

or L = L_o (1+aDT)

where L_o is the original length.

Volume Expansion

V = V_o [1 + 3aDT]

V = V_o [1 + bDT]

where b, the coefficient of volume expansion, is three times larger than a the coefficient of linear expansion.