The waterfall has
velocites in both the horizantal and vertical directions. V1 has the
same value at both positions in the graph, or equal to the flow of the
stream. V2 on top of the falls is zero at the very top because the
vertical force hasn't had time to gain any momentum, and V2 at the
bottom has gained all the momentum it will reach before hitting the
surface and has a value equal to sqrt(2*g*h). Adding the velocity
values together will give a total Velocity to a waterfall.
