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A block-spring system oscillates on a frictionless horizontal surface. The time needed for the block to complete one cycle is 0.1 sec. Determine the time needed for the block to travel from -A/2 to A/2, where A is the amplitude of motion.
A sinusoidal wave travelling in the positive x-direction has a wavelength of 0.4 m, an amplitude of 20 cm, and a period of 4 seconds. The transverse position of an element of the medium at x = 0 and t = 0 is y = 10 cm, and the element is moving downward. The expression of the wave function describing this wave is: