Australia's Science Forum

Any tips on what bells work well for demonstration of the 'Bell in a Vacuum' experiment?
Also, any suggestions on what apparatus works best e.g. Bell Jar, type of pump, etc.
Be interested to know what others are using and what works/doesn't work!

We just use an old style alarm clock, the one with the 2 bells on top. Most department stores sell them.
https://www.google.com/search?q=alarm+c ... 66&bih=625

Some of the suppliers sell bell jars with the alarm fixed inside. Downside is if you want to use the bell jar for something else, eg shaving foam, you have to unscrew the alarm to remove it.
As for pumps, the recommendation is to buy an oil free pump.

The bell disappeared from the bell jar somehow, so we put a phone in and call it. Works beautifully. We've got an oil-free pump, no brand markings on it I'm afraid.

Marama T wrote: ↑14 Nov 2019, 07:34 The bell disappeared from the bell jar somehow, so we put a phone in and call it. Works beautifully. We've got an oil-free pump, no brand markings on it I'm afraid.

That's an awesome idea Marama T
It also shows that radio waves can travel through a vacuum too .

We have an electric bell in ours but its a bit flakey ....might go the phone path next time .

We have a small bluetooth speaker (a cheap one of course!) I'm not game enough to risk exposing my very expensive phone to a vacuum!

Great idea. But how about getting the student who was using their phone in class, when they're not supposed to, to "volunteer" theirs?

Merilyn1 wrote: ↑15 Nov 2019, 08:04 Great idea. But how about getting the student who was using their phone in class, when they're not supposed to, to "volunteer" theirs?

Great idea!

Thanks All, great ideas!