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15. The displacement of a mass oscillating on a spring is given by x(t) = x_m * cos(wt + ph). If the initial displacement is zero and the initial velocity is in negative x direction, then the phase constant phi is:
16. Mass m, oscillating on the end of a spring with spring constant k, has amplitude A. Its maximum speed is
18. If the length of a simple pendulum is doubled, its period will
19. A simple pendulum is suspended from a ceiling of an elevator. The elevator is accelerating upwards with acceleration a. The period of the pendulum, in terms of its length L, g, and a is
20. Three physical pendulums, with mass m1, m2 = 2m1, and m3 = 3m1, have the same shape and size and are suspended at the same point. Rank them according to their periods, from shortest to longest.
The solution focuses on the simple harmonic motion of the spring and simple pendulum.