How to keep a Ping-Pong ball suspended in mid-air, mitigate the risk of “falling back”? We will need a hand-held hair dryer with a hose that can be attached. The dryer will blow air out instead of sucking it in. Here is how to set up your experiment for risk engineering?
- Turn on the dryer; hold it so that it blows straight up.
- Drop a Ping-Pong ball into the center of the air stream.
- Adjust the power to maintain appropriate air flow.
- The ball will dance around, being suspended in the air.
- With a little practice, we will be able to move the test setup around the room without Ping-Pong ball “falling back.”
Similar to model-test of wind-blowing, we can fly a Ping-Pong ball because the air stream goes over a curved surface and thus produces an area of lower pressure. According to the Bernoulli’s Principle, the pressure differential pulls in the Ping-Pong ball in the direction of the lower pressure.
This is similar to how we prevent London Bridge from falling down.
drjohnxwang 