The challenge is to try to fill a long thing plastic bag, of about 25cm diameter width, with air as quickly as possible. It would normally take half a minute, and that’s if you try hard. However, the Physikanten show that it can be done in a few seconds by using a physics trick.
How does it work?
It’s quite simple - you just have to open the bag and hold it open about 20cm from your mouth and blow strongly once. In the bag a fast current will be created which leads to a decrease in pressure (known as the Bernoulli-Effect). Around the opening of the bag there is air at normal air pressure, which is greater than the low pressure created inside the bag. As such, air will be sucked into the bag, and it’s suddenly full!
It is also possible to find these plastic tube bags in our store! Check it here:
www.physikantenshop.de
