Q. A string with linear density 2.0 g/m is stretched along the positive x-axis with tension 20 N. One end of the string, at x = 0, is tied to a hook that oscillates up and down at a frequency of 100 Hz with a maximum displacement of 1.0 mm. At t = 0 s, the hook is at its lowest point.

Q. A sailboat is moving across the water at 3.0 m/s. A gust of wind fills its sails and it accelerates at a constant 2.0 m/s2. At the same instant, a motorboat at rest starts its engines and accelerates at 4.0 m/s2. After 3.0 seconds have elapsed, find the velocity of (a) the sailboat, and (b) the motorboat.