## College Physics (4th Edition)

We can rank the points in order of mechanical energy, from greatest to least: $A=B=C=D=E$
By conservation of energy, the mechanical energy is constant for all points in the motion. That is, the sum of the gravitational potential energy and the kinetic energy is constant for all points in the motion. If the skier moves to a higher vertical position, the gravitational potential energy increases, and the kinetic energy decreases by the same amount. If the skier moves to a lower vertical position, the gravitational potential energy decreases, and the kinetic energy increases by the same amount. The mechanical energy is constant throughout the motion. We can rank the points in order of mechanical energy, from greatest to least: $A=B=C=D=E$