Show infect insect noten the slow flapping of a butterfly a wing produces no sound when the movements are rapid a noise is prodoc ed which increases with the Is number be r 0 of f vibrations thustle thug the housely hou bouse seli fly w which ich produces the sound of F vibrates its wings 21 times a minute or times a second and the bee which makes a sound of A as many as 26 times or times a second A tir tired 0 d bee hums on E and therefore accord ing to theory vibrates its wings only 30 times a second |