Answer:
windmill, device for tapping the energy of the wind by means of sails mounted on a rotating shaft. The sails are mounted at an angle or are given a slight twist so that the force of wind against them is divided into two components, one of which, in the plane of the sails, imparts rotation.
Step-by-step explanation:
The use of windmills was increasingly widespread in Europe from the 12th century until the early 19th century. Their slow decline, because of the development of steam power, lasted for a further 100 years. Their rapid demise began following World War I with the development of the internal-combustion engine and the spread of electric power; from that time on, however, electrical generation by wind power has served as the subject of more and more experiments
To work efficiently, the sails of a windmill must face squarely into the wind, and in the early mills the turning of the post-mill body, or the tower-mill cap, was done by hand by means of a long tailpole stretching down to the ground. In 1745 Edmund Lee in England invented the automatic fantail. This consists of a set of five to eight smaller vanes mounted on the tailpole or the ladder of a post mill at right angles to the sails and connected by gearing to wheels running on a track around the mill
The most important use of the windmill was for grinding grain. In certain areas its uses in land drainage and water pumping were equally important. The windmill has been used as a source of electrical power since P. La Cour’s mill, built in Denmark in 1890 with patent sails and twin fantails on a steel tower. Interest in the use of windmills for the generation of electric power, on both single-user and commercial scales, revived in the 1970s.