An opaque label is illuminated by lamp L and viewed through a coloured window.
| Component | Red light | Green light | Blue light |
|---|---|---|---|
| emitted by lamp L | yes | no | yes |
| reflected by the label | no | yes | yes |
| transmitted by the window | yes | yes | no |
Any light that is not reflected by the label or transmitted by the window is absorbed.
Explain why the label appears black when it is illuminated by lamp L and viewed through the window.
Lamp L is replaced by a white lamp.
Give the colour that the label now appears when viewed through the window.
93 exam-style questions on Edexcel GCSE Physics 5.1 Reflection, refraction and lenses, covering 5.1.1 Reflection, refraction and total internal reflection, 5.1.2 Specular and diffuse reflection, 5.1.3 Colour of light: absorption and filters, 5.1.4 Lenses: power, focal length and shape, 5.1.5 Ray diagrams for converging and diverging lenses, and 5.1.6 Real and virtual images. Each one has a worked solution and a mark scheme showing where the marks go.