Year 3 Science: Light bounces off surfaces
Part of the Year 3 Science light and shadows chapter. Chapter overview · whole chapter on one page
Light bounces off surfaces
Light can bounce off a surface. This is called reflection. When light is reflected, we say it is reflected from the surface.
A mirror is very smooth and shiny. It reflects a lot of light in one clear direction, so the spot on the wall is bright and clear. A dull, rough surface scatters light in many directions, so the spot is soft or faint. A dark surface reflects very little light.
Priya tested five surfaces in the same dark room, with the same torch. She shone the torch at each surface, and looked at the spot on the wall.
| Surface | Shiny or dull? | What the torch shows on the wall |
|---|---|---|
| Mirror | shiny | a clear, bright spot |
| Kitchen foil, flat and smooth | shiny | a bright spot |
| White paper | dull | a bright, soft spot |
| Wooden table | dull | a faint spot |
| Black card | dull | no spot that you can see |
Key ideas
- Light can bounce off a surface. This is called reflection.
- A mirror is a smooth, shiny surface that reflects light clearly.
- Dull surfaces scatter light in many directions, so the spot is soft or faint.
- A dark surface reflects very little light.
Method. Find the surfaces with a bright spot in the last column.
- Read the last column. The mirror, the kitchen foil and the white paper all made a bright spot.mirror, foil, paper
- Count them. Three surfaces made a bright spot.3
- Write the answer. 3
Check. The wooden table made a faint spot, and the black card made no spot. ✓
Method. Find the row that says no spot in the last column.
- Read the last column. The black card says no spot that you can see.no spot
- Write the surface. So the surface is the black card.Black card
- Write the answer. Black card
Check. A dark surface reflects very little light. ✓
Method. Look for the clear spot in the last column.
- Read the last column. The mirror made a clear, bright spot, with a sharp edge.clear, bright
- Write the surface. So the clearest spot came from the mirror.Mirror
- Write the answer. Mirror
Check. A mirror is smooth and shiny, so its reflection is clear. ✓
Watch out
Watch out: a reflection is not a light source. The mirror does not make light. It only bounces light from the torch.
Try it at home or school (with a grown-up). In a room with the curtains closed, with a grown-up, shine a torch at a small mirror. Watch the bright spot move on the wall as you tilt the mirror. Never point the torch or the mirror at anyone’s eyes. Switch the torch off when you finish.
Exam tip
Grown-up tip. Ask: “Where did the light go after it hit the mirror? Why is the spot on the wall bright?” Let your child use the words reflect, reflection and shiny.
Exercise 8C Light bounces off surfaces
Method. Find the mirror in the table.
- Read the second column. The mirror is listed as shiny.shiny
- Write the answer. shiny
Check. A mirror is very smooth. ✓
Method. Read the key ideas in this section.
- Read the definition. Light bouncing off a surface is called reflection.reflection
- Write the answer. reflection
Check. The light is reflected from the surface. ✓
Method. Find the wooden table in the table.
- Read the last column. The wooden table made a faint spot.faint
- Write the answer. faint
Check. Wood is dull, so it scatters the light. ✓
Method. Count the rows that say shiny.
- Read the second column. The mirror and the kitchen foil are shiny.mirror, foil
- Count them. There are two shiny surfaces.2
- Write the answer. 2
Check. The white paper and the others are dull. ✓
Method. Find the dull surface with a bright, soft spot.
- Read the table. The white paper is dull, and it made a bright, soft spot.White paper
- Write the answer. White paper
Check. Dull surfaces scatter the light, so the spot is soft. ✓
Method. Read the definition of a mirror.
- Read the sentence. A mirror is very smooth and shiny.shiny
- Write the answer. shiny
Check. Shiny surfaces reflect light clearly. ✓
Method. Look at the picture.
- Read the picture. The arrow from the torch hits the mirror, and another arrow leaves it.arrow leaves
- Write the answer. yes
Check. The light is reflected, and the spot is bright. ✓
Method. Think about where the light comes from.
- Think about the mirror. A mirror only bounces light from a light source; it does not make light.bounces
- Write the answer. false
Check. The torch is the light source. ✓
Method. Look at the black card in the table.
- Read the table. The black card made no spot that you can see.no spot
- Decide. Dark surfaces reflect very little light, so Ali is not right.no
- Write the answer. no
Check. A dark surface does not reflect much light. ✓
Method. Think about which surfaces reflect light clearly.
- Think about the choice. A shiny surface reflects light clearly, in one direction.shiny
- Make the choice. So a mirror or kitchen foil is a good choice.mirror or foil
- Write the answer. Accept any shiny surface, such as a mirror or kitchen foil.
Check. A test would show whether the spot reaches the corner. ✓
Method. Think about the two surfaces.
- Think about the paper. White paper is dull, so it scatters the light in many directions.scatters
- Think about the mirror. A mirror is shiny, so it reflects the light in one clear direction.one clear direction
- Write the answer. Accept any sentence that says white paper is dull and scatters light in many directions, but a mirror reflects light in one clear direction.
Check. Shiny surfaces give clear reflections, and dull surfaces give soft ones. ✓