Figure 1 shows two boiling tubes, a radiant source of heat, and other laboratory equipment.

The boiling tubes absorb thermal radiation from the heater.
One boiling tube is wrapped in matt black paper and the other boiling tube is wrapped in shiny silver foil.
Both tubes contain the same volume of water at the same initial temperature.
Describe how a student could use the apparatus in Figure 1 to determine which surface is the better absorber of thermal radiation.