The windmill is designed according to the lever principle and is a unidirectional rotating machine. The blades of the wind turbine are rotationally symmetrical and not axially symmetrical. When there is wind, the twisting moments generated by the blades in symmetrical positions cannot cancel each other, so part of the wind energy is retained by the wind turbine and the wind turbine can rotate.
The windmill blades are all inclined. Windmills use wind as energy. When the wind blows on the blades, it is equivalent to exerting force on the blades to generate rotational torque. the windmill turns. It will continue to spin.
:A wind turbine, also called a wind turbine, is an electrical machine that does not require fuel and uses wind as energy. Ancient windmills developed from sails. They had 6 to 8 sail-shaped canopies, distributed around a vertical axis, when the windblew, they rotated around the axis like a rotating lantern.