kuşların özellikleri

Released until it reaches a certain speed, the sound of the train because the movement of the wheels on the rails. However, speed 200 km / h when the actual source of the sound of the train movement of air in the resulting aerodynamic noise. Aerodynamic noise, the number one factor in formation of the electrical wire is used to retrieve the top pantographs or current collectors. Normally, the engineers used a rectangular-shaped difference pantograflarla azalmayacağını noise, intensified research on living things moving fast, but quiet. Japanese researchers have realized that as a result of the work on living things in all the silent flight of birds, the owl will perform