Good set of lungs
This is a good one but it takes some work to pull it off.
1. Balance a penny flat on the top of an upright glass.
2. Now try to blow the coin in such a way that it blows over the glass. It’s impossible unless you know the trick.
3. Here’s the trick, blow over the penny. If you can blow straight over the
penny, the Bernoulli principle will lift the penny and send it shooting over the
other side of the glass. This is quite tough but once you get the hang over it
it’s a lot of fun to show other folks.