Question

A student is investigating the kinetic and potential energy transformations that occur when a

skateboarder rides back and forth on a half-pipe skate ramp, as shown below. Initially, the
skateboarder is standing at rest on the upper edge of the half-pipe. Then, he drops in, rolls
toward the bottom of the ramp, rolls up the opposite side, and finally rolls back to his starting
position. (Assume there is no energy lost to friction during his rides.)
Describe the transfer of potential and kinetic energy as he moves from the top of the ramp to
the opposite side and back to starting position.

Answer 1

Starting point of the ramp - Potential energy is maximum, Kinetic Energy is minimum.

Midway through the ramp - Potential energy is minimum, Kinetic Energy is maximum.

End of ramp - Potential energy is maximum, Kinetic Energy is minimum.

Step-by-step explanation:

A.

Starting point of the ramp - Potential energy is maximum, Kinetic Energy is minimum.

The P.E is maximum because the skater is at the maximum elevation above the earth's surface, hence the P.E which is equals to m X g X h is maximum. The K.E is minimum because the velocity of the skater is equals to zero.

B.

Midway through the ramp - Potential energy is minimum, Kinetic Energy is maximum.

As the skater rolls down the ramp all his P.E gets converted into K.E. as he loses elevation. His point of maximum Kinetic energy will be midway through the ramp, when he has lost all his potential energy due to his former elevation. This point is also known as the lowest point on the ramp.

C.

End of ramp - Potential energy is maximum, Kinetic Energy is minimum.

As the skater climbs back the other side of the ramp, he begins to gain elevation as his speed reduces again. This means that his Kinetic energy is being converted to Potential energy. This stops when he is at the top of the ramp and all his K.E is gone