·         Heat is a form of Energy.

·         Heat means Heat Energy.

·         Temperature measures the degree of hotness or coldness of a body.

·         When a body or object gains heat its temperature increases.

·         When a body or object loses heat its temperature decreases.

Units For Measuring Heat

Expansion of Solids

Conceptual Points

·         Solids on heating (generally).

·         Expansion means increase in dimensions (size) of the solid.

·         Solids are of three types

A)One Dimensional (1-D)

B)Two Dimensional (2-D)

C)Three Dimensional (3-d)

·         A 1-D solid has only one prominent or significant dimension i.e. length

·         A two dimensional solid has only two prominent or significant dimensions i.e. length and breadth

·         A three dimensional solid has three prominent or significant dimensions i.e. length, and height

·         Linear Expansion is only possible in case of one dimensional solids on heating.

·         Areal Expansion or Superficial Expansion occurs in case of two dimensional solids on heating.

·         Volume Expansion or Cubical Expansion occurs in case of three dimensional solids on heating.

·         One dimensional solid size means length.

·         Two dimensional solid size means area.

·         Three dimensional solid size means volume.

Types of Expansion in solids