A hollow metal cube is filled with hot water. Each of the four vertical faces has a different surface. A student pointed an infrared detector at each face in turn, from the same distance.
Table: Infrared detector reading for each of the four faces of a metal cube filled with hot water
| Face | Surface of the face | Detector reading in arbitrary units |
|---|---|---|
| W | matt black | 92 |
| X | matt white | 71 |
| Y | shiny black | 60 |
| Z | shiny silver | 18 |
Which conclusion is supported by these readings?
A shiny surface is a better emitter of infrared radiation than a matt surface.
A black surface is a better emitter of radiation than any other surface.
All four of the faces emit infrared radiation at exactly the same rate.
A matt surface is a better emitter of infrared radiation than a shiny surface.
40 exam-style questions on AQA GCSE Physics 6.3 Black body radiation, covering 6.3.1 Emission and absorption of infrared radiation and 6.3.2 Perfect black bodies and radiation. Each one has a worked solution and a mark scheme showing where the marks go.