Which point does the skateboarder have the highest amount of stored KE?

Question

Look at the simulation of the skateboarder on the half pipe. At which point(s) (A, B, C) does the skateboarder have the HIGHEST amount of stored KE, or is there NO KE?  

Answer 1

First recognize that the total energy of the skater is conserved: this means that the total energy of the skater is constant. The total energy (E) consists of the kinetic energy (KE) and gravitational potential energy (Ug).

E=KE+Ug

Now we know that the gravitational potential energy depends on the distance from the zero of potential (or in simpler terms: how high the skater is from the ground). Now, we are ready to answer the question.

The skater possesses the most KE at point B: remember total energy is a constant and at point B the skater has the least amount of potential energy (since they are at their lowest point above the ground). This means that the skater must have more kinetic energy at point B.

Similarly, at points A and C, the skater possesses the most potential energy since they are at their highest point above the ground.