| A | B |
|---|
| In straight lines | How does light travel? |
| 300 000 000 m/s | What is the speed of light in a vacuum? |
| Luminous | What are objects that give out light on their own called? |
| Non-luminous | What are objects that do not give out light on their own called? |
| Transparent | What are objects that allow almost all light to pass through called? |
| Opaque | What are objects that do not allow light to pass through called? |
| Transluscent | What are objects that allow almost some light to pass through and scatters the rest called? |
| Ray | What is the path which light travels? |
| Beam | What is a bundle of rays? |
| Umbra | What is the totally dark shadow formed by a point source of light? |
| Penumbra | What is the partially dark shadow formed by an extended source of light? |
| Solar eclipse | When the Moon is between the Sun and the Earth, in a straight line, what is formed? |
| Lunar eclipse | When the Earth is between the Sun and the Moon, in a straight line, what is formed? |
| Pinhole camera | What is the simple device to demonstrate that light travels in straight lines and produces images that are real, inverted and same colour as the object? |
