A trolley is at rest, tethered between two springs. It is pulled 0.15 m to one side and, when time t = 0, it is released so that it oscillates back and forth with s.h.m. The period of its motion is 2.0 s.
a. Write an equation for its displacement x at any time t (assume that the motion is not damped by frictional forces).
b. Sketch a displacement–time graph to show two cycles of the motion, giving values where appropriate.