- Historically, windmills were used to do work. The spinning blades would harness the force of the wind and use it to turn a millstone, which would grind grains. Nowadays, however, this practice is almost completely unheard of. Windmills are making a comeback, but they are being used to generate electricity instead of mechanical power.
- Windmills work in a similar way to sails or propellers. The wind hits the blades of the windmill at a diagonal angle and is channeled along the curve of the blade to the side. This moving air pushes the blade in the opposite direction, causing it to spin. At the same time, the moving air creates a low-pressure area at the front of the blade, creating lift that pulls the blade forward. The blades turn a shaft, which is attached to a generator.
- Most electrical generators work in pretty much the same way. A magnet is attached to a shaft surrounded by coils of wire. As the shaft turns, it spins the magnet, which creates a moving magnetic field in the wire. This moving magnetic field creates a moving electrical current in the wire, which then can be used to help light lights and power appliances.
