Science 5 · Unit 5: Forces and magnetism · Cambridge Primary Science Stage 5

Questions

1. 1. Sofia rolls a ball. Which forces slow it down once it is moving?

   • the normal force only
   • air resistance and friction
   • gravity and upthrust
   • thrust and lift
   Check

2. 2. What is thrust?

   • a force that slows things
   • a force that pulls things down
   • the upward push of water
   • an applied force that pushes something forwards
   Check

3. 3. Which force pushes up on an aeroplane's wings?

   • gravity
   • drag
   • friction
   • lift
   Check

4. 4. Which force pushes an aeroplane forward?

   • drag
   • thrust from the engines
   • lift
   • gravity
   Check

5. 5. What are the four forces on a flying aeroplane?

   • upthrust, friction, normal force and magnetism
   • only gravity and lift
   • lift, gravity, thrust and air resistance
   • thrust and nothing else
   Check

6. 6. Which two forces on an aeroplane are natural forces?

   • lift and air resistance
   • thrust and lift
   • gravity and air resistance
   • thrust and gravity
   Check

7. 7. Why is it harder to cycle when the wind blows into your face?

   • The road has less friction.
   • There is less gravity.
   • There is more air resistance.
   • There is more upthrust.
   Check

8. 8. Why do cyclists with smooth tyres travel faster on a smooth road?

   • There is more air resistance.
   • There is more gravity.
   • There is more upthrust.
   • There is less friction.
   Check

9. 9. How do racing cyclists overcome air resistance?

   • They crouch low and wear tight clothes and streamlined helmets.
   • They pedal backwards.
   • They wear loose flapping clothes.
   • They sit up tall.
   Check

10. 10. Which force causes an object's change when many forces act?

    • the weakest force
    • the newest force
    • the first force
    • the strongest force
    Check

11. 11. A paper aeroplane is resting on a table. Which forces act on it?

    • thrust and lift
    • gravity and the normal force
    • air resistance only
    • no forces at all
    Check

12. 12. Why does a paper aeroplane eventually crash to the ground?

    • Gravity and air resistance win once the thrust from the throw runs out.
    • It runs out of fuel in its engine.
    • The air pushes it down.
    • Paper is magnetic.
    Check

13. 13. A swimmer moves through water. Which force must they create to move forward?

    • more water resistance
    • more upthrust only
    • thrust, by pushing against the water
    • more gravity
    Check

14. 14. Which three natural forces act on a swimmer?

    • gravity, upthrust and water resistance
    • friction with the floor, lift and thrust
    • only gravity
    • thrust, lift and magnetism
    Check

15. 15. A submarine moves through water. What causes its thrust?

    • gravity
    • upthrust
    • water resistance
    • its propeller and engine
    Check

16. 16. How does a bird overcome gravity and air resistance to fly?

    • It gets heavier.
    • It flaps its wings to make lift and thrust.
    • It uses upthrust from water.
    • It stops moving.
    Check