Question

-What can you say about the snowboarder’s kinetic energy as he moves?

Answer 1

Answer:

  His kinetic energy increases, potential energy decreases

  The sum of kinetic and potential energy is a constant at any instant before he comes to rest.

Explanation:

  Snowboarder is starting from a height and moving to the down direction. As he moves down his velocity increases, we know that kinetic energy is given by the expression $\frac{1}{2} mv^2$, so as he moves his kinetic energy increases.

  When the snowboarder is starting his potential energy is maximum(Potential energy = mgh), as he comes down his potential energy decreases.

  Based on this we can conclude that the sum of potential energy and kinetic energy is a constant at any instant for a snowboarder before he comes to rest.

                             mgh+$\frac{1}{2} mv^2$= Constant