1- If the phase angle for a block-spring system in SHM is pi/6 rad and the block's position is given by x = xm cos(wt + pi). what is the ratio of the kinetic energy to the potential enery at time t = 0?
2- A physical pendulum consists of a meter stick that is pivoted at a small hole drilled through the stick at a distance d from the 50 cm mark. The period of oscillation is 2.5 s. Find d.
3- Two particles excecute simple harmonic motion of the same amplitude and frequency along close parallel lines. They pass each other moving in opposite directions each time their displacement is half their amplitude. What is their phase difference?