Discuss the changes in potential energy and kinetic energy and total energy for skateboarder going up and down on a half pipe ramp

In regards to basic motion, the total energy is simply the sum of potential energy and kinetic energy. Potential energy is dependent with position.

Going up:

Potential energy increases, Kinetic energy decreases, Total energy is constant

Going down:

Potential energy decreases, Kinetic energy increases, Total energy is constant

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.

total distance/total time

(85 + 82)/(5+3)

167/8

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