If a substance is heated or cooled, the linear expansion occurs along the axis is

Options

A. X or- X
B. Y or- Y
C. both (a) and (b)
D. (a) or (b)

Answer

C

Explanation

When substance is heated its expansion is positive i.e., can be taken along either +X or + Y direction. But when substance is cooled its either length, or area or volume decreases i.e. with respect expansion it is opposite direction i.e. either-X or -Y direction respectively,