Homework Activity: Homemade Hovercraft (Forces)

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Science homework Key Stage 3: Homemade Hovercraft.

If you’re teaching forces this term, here’s a simple science homework activity for Key Stage 3 that will get your students exploring forces, weight and friction.

Each student will need:

  • 10 cm x 10 cm square of fairly thick cardboard
  • 1 used cotton reel, one of the short, fat ones with a small hole running through the middle (you need the wooden or plastic reel, not the cotton)!
  • Some non-toxic glue
  • 1 balloon
  • 1 pencil or pen
  • 1 ruler

How to build your hovercraft

Student instructions

  1. Use your ruler to draw a cross on one side of the cardboard square. Draw one straight line through one corner to the opposite corner. Draw another straight line joining the other opposite corner
  2. The lines should cross in the centre of the cardboard.
  3. Use your pencil or pen to push a small hole through the centre of the cardboard.
  4. Place the cotton reel flat-side-down on the cardboard so that the hole through it lines up with the hole you have made in the cardboard.
  5. Mark where the reel needs to go on the cardboard.
  6. Put some glue around the flat side of the reel in a circle; make sure it is not too close to the hole.
  7. Stick the reel to the cardboard so the holes line up and leave it to dry.
  8. Test that air is coming through the hole by blowing through it.
  9. Stretch the open end of the balloon over the end of the cotton reel so that it seals tightly all the way round the top of the reel.
  10. Inflate the balloon by blowing through the hole in the cardboard.
  11. When the balloon is fully inflated, hold the hole in the cardboard closed with your finger.
  12. Place your hovercraft cardboard-side-down on a smooth surface like a kitchen worktop and release your finger from the hole, so the air rushes out of the balloon.
  13. Your hovercraft should float over the top of the worktop! (If it doesn’t, what do you think you need to change to make it work?)

Alternative method

You can use an old CD and the waterproof sports cap from a water bottle instead of the cotton reels and cardboard.

  • Take the cover off the lid and pop it shut.
  • Use glue or blu-tack to stick the bottle cap over the hole in the CD.
  • Blow up a balloon and place the opening over the top of the bottle cap.
  • Place it on a smooth surface and open the bottle cap. Your hovercraft should move around!

Try to explain what is happening. Think about forces, weight and friction.

 

 

 

 

Exploring forces this term with your students? Here are some more free resources …