Head back to the future with this easy to make, tabletop hovercraft!
You will need:
An old CD or DVD disc
A pop-top cap from a water bottle or similar
Cover the center hole of the disc with some sellotape and poke some small holes in the tape. This will slow down the flow of air and allow your hovercraft to hover longer.
Super glue the cap to the center of the disc, over the hole. Leave for 20-30 minutes to allow to dry.
Blow up the balloon but don’t tie it.
Make sure the cap is closed and fit the neck of the balloon over the cap.
Put the hovercraft on a smooth surface, pop open the cap, and watch it hover!
The science bit:
The air coming out of the balloon causes a cushion of moving air between the disc and the surface. This lifts the disc and reduces the friction which allows it to hover freely.
What happens if you use a different shaped balloon?
Thanks to Science Bob for this experiment!