posted by Help .
A buoy oscillates in simple harmonic motion according to the motion of waves at sea. An observer notes that the buoy moves a total of 6 feet from its lowest point to its highest point. The buoy returns to its highest point every 15 seconds.
Amplitude: 6 feet
Period: 2pi/15, or one oscillation every 15 minutes.
Equation: let d be the displacement then
d = 6cos(2pi/15t)