Question

A whistle emitting a sound of frequency `440 H`z is tied to string of `1.5 m` length and rotated with an angular velocity of `20 rad//sec` in the horizontal plane. Then the range of frequencies heard by an observer stationed at a large distance from the whistle will `(v=330 m//s)`

Answer 1

`v_S=romega=1.5xx20=30(m)/(s)`
`n_(min)=(v)/(v+v_S)n=(330)/(330+30)xx440Hz=403Hz`
`n_(max)=(330)/(330-30)xx440=484Hz`