Question: A wave travels along a canal. Let x be the distance along the canal, t be the time, and z be the height of the water above the equilibrium level. The graph of z as a function of x and t is in Figure.
(a) Draw the profile of the wave for t = -1, 0, 1, 2. (Put the x-axis to the right and the z-axis vertical.)
(b) Is the wave traveling in the direction of increasing or decreasing x?
(c) Sketch a surface representing a wave traveling in the opposite direction.
