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.
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.
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.
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.