In an AC system, the pedastal fan in your bedroom is electromagnetically coupled to the turbine at the coal/gas/hydro/nuc power station. They instantly and directly influence each other, and they both are spinning in tandem like two wheels on a car connected by an axel. Slowing the rotation of the fan with your hand technically increases the torque of the turbine, if only by an immeasurably small amount.
Fun Fact: An improperly shielded (or old and deteriorating) fan can be influenced by stray electromagnetic radiation. They’ll pick up AM radio signals occasionally, creating an off tone in the fan noise that sounds like a person talking faintly on the other side of the fan.
AC motors are more powerful but also more noisy. You need that power in your kitchen mixer but you need quiet in a fan. Modern WC rooms now have a DC fan, old ones have the loud one.
In an AC system, the pedastal fan in your bedroom is electromagnetically coupled to the turbine at the coal/gas/hydro/nuc power station. They instantly and directly influence each other, and they both are spinning in tandem like two wheels on a car connected by an axel. Slowing the rotation of the fan with your hand technically increases the torque of the turbine, if only by an immeasurably small amount.
Fun Fact: An improperly shielded (or old and deteriorating) fan can be influenced by stray electromagnetic radiation. They’ll pick up AM radio signals occasionally, creating an off tone in the fan noise that sounds like a person talking faintly on the other side of the fan.
AC motors are more powerful but also more noisy. You need that power in your kitchen mixer but you need quiet in a fan. Modern WC rooms now have a DC fan, old ones have the loud one.