Question

Write three different applications of expansion and contraction of materials.

Answer 1

Following are the applications of expansion and contraction of materials:

1. The jammed metal lid of a jam jar can be expanded and opened by heating.
2. In many thermometers, mercury is used. When the bulb of the thermometer comes in contact with a hot object, the mercury expands and its level rises in the glass tube, indicating the temperature.
3. The electric lines are never hung tautly between poles because in outside environment wires are subjected to extreme weather conditions, ranging from acute hot to cold temperature. In winters, a taut wire on contraction can snap.