Practise explaining thermal expansion through changes in molecular separation and intermolecular forces with CAIE IGCSE Physics questions and mark schemes.
A quantity of gas is trapped by a piston in a cylinder with thin metal walls. The piston is free to move without friction within the cylinder.
Fig. 4.1 shows the cylinder and piston.
Fig. 4.1
The cylinder is placed inside a freezer.
As the temperature of the metal cylinder decreases, the volume of the metal decreases. The decrease in the volume of the metal is much less than the decrease in the volume of the gas.
Explain, in terms of the particles of the metal, why the decrease in the volume of the metal is less than that of the gas.