The speed of a wave travelling along a 0.650 m guitar string is 320 m/s at n = 5 the frequency is 1230 Hz. What is the frequency of a string wave speed of 240.0 m/s is used?

Aplayground merry-go-round has a radius of 4.6 m and a moment of inertia of 200 kg-m2 and turns with negligible friction about a vertical axle through its center. a child applies a 26.0 n force tangentially to the edge of the merry-go-round for 15.0 seconds. if the merry-go-round is initially at rest, how much work did the child do on the merry-go-round?