(hovercraft) . Plan and undertake experiments or research in two of the following areas. Show you understand the science behind what you have done. A) Weather - learn about predicting, measuring and preparing for weather. b) Crime Scene Investigation – find out what happens when a crime is being investigated. c) World of the future – how do developments in science and engineering improve the way we live? d) Flash, bang, goo – can mixing things change what they do? e) Night Sky – identify 3 constellations and the legends connected with them.
An old CD or DVD disc
A 9” balloon
A pop-top cap from a liquid soap bottle or a water bottle
Aim of Badge: To encourage an interest in science
This Badge has 2 options with sub divisions of which two sub divisions must be completed from option 1 and one sub divisions from option 2
d) Flash, bang, goo – can mixing things change what they do?
If you are using the cap from a water bottle, cover the centre hole of the CD with a piece of tape and poke about 6 holes in the tape with a push-pin or small nail. This will slow down the flow of air and allow your hovercraft to hover longer.
Use the hot glue gun to glue the cap to the centre of the CD or DVD disc. Create a good seal to keep air from escaping.
Blow up the balloon all the way and pinch the neck of it. (Don’t tie it.)
Make sure the pop-top is closed and fit the neck of the balloon over the pop-up portion of the cap. (This is usually easier with 2 people)
That’s it! When you are ready to commence hovering, simply put the craft on a smooth surface and pop the top open.
How does it work: The air flow created by the balloon causes a cushion of moving air between the disc and the surface. This lifts the CD and reduces the friction which allows the disc to hover freely. Large scale hovercraft are capable of traveling over land, snow and water.
Make it an experiment: The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:
1. Does the size of the balloon affect the CDs ability to hover?
2. Does a helium balloon work better than an air filled balloon?
3. Do larger discs make better hovercrafts (plastic picnic plates, old record albums)?
Trefoil News Spring Edition 2017