Relation among coefficient of volume expansion of matter  γReal=γR,γapparent=γa&γglass=γg is (γReal is real expansion of liquid, γapparent is apparent expansion of liquid,γglass is volume expansion of glass)

when a container with liquid is heated , initially level of liquid falls due to expansion of container alone and not liquid, then liquid expands hence level of liquid in container now raises, in this experiment we can observe that over all expansion is real expansion between fall and raise of liquid levels