You are midway up hill A in Figure P9.75. Across the valley is the shorter hill (B),

Question:

You are midway up hill A in Figure P9.75. Across the valley is the shorter hill $B$, the summit of which is slightly higher than your present spot. You want to roll a ball so that it crests hill B. To get the ball moving, you can roll it either up or down hill A, giving the ball the same initial speed in both cases.

(a) Which roll direction is more likely to get the ball to crest B, or does it matter? Ignore any energy dissipation.

(b) In what way would your answer change if you take energy dissipation into account?

Data from Figure P9.75