Question

Explain thermal expansion with suitable examples.

Answer 1

The expansion of a substance on heating is called, the thermal expansion of those substances.

1. Gaps are left in between rails while laying on a railway track. The reason is during summer thermal expansion takes place.
2. Gaps are left in between two joints of a concrete bridge because of thermal expansion.
3. Electric wires between electric posts contract on cold days and sag in summer.
4. By fitting the iron rim on the wooden wheel they will heat the iron rim expansion takes place. They will fit with the wheel when the rim is cold, it will not slip.
5. Riveting: To join two steel plates together, a hot rivet is driven through the hole of the plates.