2. Exciting waves. (10 points: 5+3+2)

a) Why is it difficult to walk carrying a bowl of soup without spilling any? Be quantitative. [Hint: make use of the shallow water wave phase velocity derived in class, and the previous problem about walking.]

b) Estimate the energy per unit area stored in ocean waves. Express your answer in terms of seconds of solar insolation.

c) Estimate the energy per unit area in the winds that drive the ocean waves. Again express your answer in terms of seconds of solar insolation.