Why do ceiling fans get dusty?
The latter is the case for ceiling fans.
As the blades rotate, they experience frictional forces as they `rub' against the air; this knocks electrons around, causing the blades to build up a net charge.
The charged dust particles then stick to the charged areas of the blades.
How does a helicopter work?
In order to fly, an object must have "lift," a force moving it upward.
A helicopter's rotor blades are wings and create lift. An airplane must fly fast to move enough air over its wings to provide lift.
A helicopter moves air over its rotor by spinning its blades.