Science 6 · Unit 5: Forces and electricity · Cambridge Primary Science Stage 6

Questions

1. 1. What is mass?

   • the pull of gravity on an object
   • the size of an object
   • how fast an object moves
   • the amount of matter in an object
   Check

2. 2. What is weight?

   • the amount of matter in an object
   • the force on an object caused by gravity
   • the volume of an object
   • the length of an object
   Check

3. 3. What unit is mass measured in?

   • kilograms (kg)
   • metres (m)
   • newtons (N)
   • volts (V)
   Check

4. 4. What unit is weight measured in?

   • newtons (N)
   • litres (l)
   • kilograms (kg)
   • grams (g)
   Check

5. 5. Which instrument measures weight?

   • a ruler
   • a measuring jug
   • a thermometer
   • a forcemeter
   Check

6. 6. A nurse says a baby 'weighs 3.6 kg'. What should she say to be scientifically correct?

   • The baby has a mass of 3.6 kg.
   • The baby has a weight of 3.6 kg.
   • The baby weighs 3.6 N.
   • The baby is 3.6 m long.
   Check

7. 7. On Earth, what is the weight of 1 kg?

   • about 1 N
   • about 0.1 N
   • about 10 N
   • about 100 N
   Check

8. 8. A brick has a mass of 1 kg. What is its weight on Earth?

   • 100 N
   • 10 N
   • 1 N
   • 1 kg
   Check

9. 9. A bag of books weighs 25 N on Earth. What is its mass?

   • 25 kg
   • 0.25 kg
   • 250 kg
   • 2.5 kg
   Check

10. 10. Does an astronaut's mass change on the Moon?

    • Yes, it gets smaller.
    • Yes, it gets bigger.
    • No, mass stays the same everywhere.
    • Yes, it becomes zero.
    Check

11. 11. Why does an astronaut weigh less on the Moon?

    • There is more air.
    • The Moon's gravity is weaker because it has less mass than Earth.
    • The astronaut loses matter.
    • The Moon is hotter.
    Check

12. 12. Mr Large has a mass of 90 kg. On Planet Zogg gravity is half as strong. What is his weight there?

    • 90 kg
    • 450 N
    • 900 N
    • 45 N
    Check

13. 13. Why do astronauts in the Space Station feel weightless?

    • They are falling around the Earth at the same rate as the station.
    • There is no gravity in space at all.
    • They have no mass.
    • They are very light.
    Check

14. 14. Why must astronauts exercise for two hours a day in space?

    • To stay warm.
    • Weightlessness makes their muscles and bones weaker.
    • To make gravity.
    • To lose mass.
    Check

15. 15. What is rehabilitation for astronauts returning to Earth?

    • a kind of rocket
    • a type of forcemeter
    • re-training their bodies and rebuilding strength
    • a space meal
    Check

16. 16. If you pull down on an object hanging from a forcemeter, is the reading its true weight?

    • Yes, always.
    • Yes, if you pull gently.
    • No, your pull adds extra force.
    • No, it shows mass instead.
    Check