Science 3 · Unit 3: Light and shadows · Cambridge Primary Science Stage 3

Questions

1. 1. Is clean water transparent or opaque?

   • transparent
   • opaque
   Check

2. 2. How might transparent water become opaque?

   • mixing lots of mud into it
   • cooling it a little
   • putting it in a glass
   • stirring it with nothing in it
   Check

3. 3. Which object is transparent?

   • a block of wood
   • a rock
   • an egg shell
   • a magnifying glass
   Check

4. 4. Which object is opaque?

   • an egg shell
   • a plastic window
   • a glass lamp
   • clear plastic
   Check

5. 5. Why are dark sunglasses no help indoors?

   • They only work at night.
   • They are opaque.
   • It is not bright indoors, so they make it too dark to see.
   • They make things brighter indoors.
   Check

6. 6. Why do a snowboarder's goggles need to be a little opaque?

   • so nobody can see their eyes
   • The Sun on the snow is very bright and could hurt their eyes.
   • to keep warm
   • to keep out snowflakes only
   Check

7. 7. Why should goggles not be too opaque?

   • They would be too heavy.
   • They would make light.
   • They would melt.
   • The person still needs to see.
   Check

8. 8. Zara adds more layers of coloured plastic. What happens?

   • The view gets darker.
   • The view gets brighter.
   • Nothing changes.
   • The plastic becomes a light source.
   Check

9. 9. Why do astronauts need very dark visors?

   • Space is very dark.
   • So they can see at night.
   • The Sun is very bright in space.
   • To keep their faces warm.
   Check

10. 10. If you wore an astronaut's visor in class, how would the room look?

    • the same as always
    • very dark
    • very bright
    • coloured rainbow
    Check

11. 11. Which place needs very dark sunglasses?

    • reading indoors
    • a dark room
    • a cloudy evening
    • a very bright sunny winter day with snow
    Check

12. 12. Which place needs no sunglasses?

    • reading indoors
    • outside on a bright day
    • a bright snowy day
    • a sunny beach
    Check

13. 13. Should you look at the Sun if you are wearing sunglasses?

    • Yes
    • No
    Check

14. 14. Why are glasses and goggles made from transparent materials?

    • so they are heavy
    • so we can see clearly through them
    • so they make shadows
    • so they block all light
    Check

15. 15. You are buying curtains to make the classroom dark. What kind of material should they be?

    • opaque
    • translucent
    • transparent
    Check