An electric laboratory heating element glows red when current passes through it. The manufacturer's manual states:
"The element glows to emit visible light and also emits a second type of radiation which transfers thermal energy outwards by radiation."
State the name of the region of the electromagnetic spectrum that transfers thermal energy.
State:
one similarity between visible light and the radiation identified in (a).
State:
one difference between visible light and the radiation identified in (a).
Some surfaces are better at absorbing radiation than others.
Describe an experiment to show whether a matt black surface or a shiny silver surface is the better absorber of radiation.
State two variables in the experiment you described that must be kept identical during the test to ensure a fair comparison.
301 exam-style questions on CIE IGCSE Physics 2.3 Transfer of thermal energy, covering 2.3.1a Thermal conductors and thermal insulators, 2.3.1b Explaining thermal conduction, 2.3.2 Convection, 2.3.3a Thermal radiation, 2.3.3b Surface colour and texture, 2.3.3c Rate of emission and absorption of radiation, and 2.3.4 Consequences of thermal energy transfer. Each one has a worked solution and a mark scheme showing where the marks go.