Ignite a paper teabag to launch a rocket upwards (adult supervision).
What you need:
Tea bag, scissors, matches
What to do:
1. Remove the staple from the tea bag and pour out the tea.
2. Straighten out the bag and smooth it out so it forms a cylinder that can stand up on its end.
3. Stand the tea bag on a plate. Use matches or a lighter to light the top of the bag.
What happens:
When the top of the teabag is lit, the air temperature within the cylinder increases. As the temperature rises, the warm air inside the cylinder becomes less dense than the cooler one outside. Less dense fluids float in a surrounding denser fluid, which implies that the warm air rises.
When most of the cylinder has burnt, it is light and does not require much force to lift it. It can take off thanks to the warm air rising.
The fact that warm air rises is used to make air balloons fly.
In nature, some birds use such warm airstreams to go up in altitude without much effort.
Back to Home Science activities.
—this homescience activity written by FLEET PhD candidate Olivier Bleu (Monash)