An iron collar needs to be fitted tightly around a cylindrical stone pillar to reinforce it. At room temperature, the inner diameter of the collar is slightly smaller than the diameter of the pillar.
Which action would make it easiest to fit the iron collar over the stone pillar?
Cooling the iron collar
Heating the iron collar
Heating the stone pillar and cooling the iron collar
Heating the stone pillar but not heating or cooling the iron collar
96 exam-style questions on CIE IGCSE Physics 2.2.1 Thermal expansion of solids, liquids and gases. Each one has a worked solution and a mark scheme showing where the marks go.