Question

Which type of wind mills blade are made out of cloth?

(a) Horizontal axis with two aerodynamic blades

(b) Horizontal axis propeller type wind mill

(c) Horizontal axis multi bladed type wind mill

(d) Sail type wind mill

This question was posed to me during an interview.

My question comes from Horizontal Axis Wind Mill in portion Wind Energy of Energy Engineering

Answer 1

Right choice is (d) Sail type wind mill

For explanation: The blade surface of sail type wind mill is made of cloth, nylon or plastics arranged as mast and pole or sail wings. There is also variation in the number of sails used. Sails are found in different designs, from primitive common sails to the advances patent sails.