how is energy finally stored into a fan
Answers
Answer:
A fan converts mechanical energy in the form of a rotating shaft, into mechanical energy in the form of kinetic energy of the fluid medium (usually air), by means of a pressure differential. This means that the fan moves air by creating low pressure at the intake, and high pressure at the exhaust.
A fan always uses mechanical energy, that's why, when you turn it off, it eventually stops spinning, and it would even if it were frictionless, because the built up mechanical energy (rotational kinetic energy) gets used up from continuing to move air.
Wherever the mechanical energy came from, you could also say is being used. For example, fans in your house, use electrical energy by first converting it to mechanical energy. A fan powered by a gas engine uses chemical energy. An aircraft carrier propeller uses nuclear energy. But again, in all these cases the fan directly uses mechanical energy.