1H10.25 - Rotational Lift
To demonstrate how a helicopter is able to lift off of the ground and stay in flight while up in the air.
Check the batteries in the remote control.
With the power switches turned on, set the UFO onto the lecture bench. Using the remote control, start the blades turning and watch as the UFO lifts off of the surface of the table. Explain to the students how there are two things helping it lift off of the table. 1) The air that hits the blades is deflected downward, lifting the UFO off of the table. This accounts for 25% of the lift. 2) The second action applys "Bernoulli's Principle" as air flows over a curved surface, it speeds up but loses pressure. With an area of low pressure sitting above the blade and the area of high pressure sitting below the blade, the high pressure wants to move towards the low pressure like a magnet, and generates lift in the process. This accounts for 75% of the lift.