Volumetric Thermal Expansion

This model shows us an apparatus for demonstrating thermal expansion, comprising a captive brass ball on a spring secured to a stand by a mounted brass ring. The metal ball fits in the hole in the ring. If the ball was heated or the ring cooled, it would not fit anymore. The account of the expansion of materials is always taken in the construction of railways and in the building of bridges and houses. When something gets hotter, it slightly increases in size or volume. The ball is heated thus it expands to the point where it no longer fits through the ring.