Living with the expansion of solids
The expansion of solids has to be allowed for, and it can be put to use.
Iron rims on cart wheels
The rim is made a little smaller than the wooden wheel, heated until it expands enough to fit, then cooled so it shrinks tight onto the wheel.
Gaps between rails
A small gap is left so that rails expanding in the heat do not buckle into each other and derail a train.
Slack wires
Telephone and power wires are hung slack so that when they contract in the cold they do not snap.
A stuck bottle cap
Warming a metal cap loosens it: for the same temperature change metal expands more than glass.
Figure to be added
Assignment 9.1
Find other situations in which the expansion of solids is useful, and write notes on them.