RipStik as demonstrator of potential converting to kinetic energy

In a rather overly simplistic physics demonstration of gravitational potential energy and kinetic energy, I used a RipStik at the bottom of a hill to show I had no potential for motion - no energy due to my gravitational position. 

Then I moved up slope and mounted up onto the caster board without pushing off with my foot. 

I then accelerated down slope, trading gravitational potential energy for kinetic energy. I then carved around on the board and noted that I could not gain speed going uphill. I was now trading kinetic energy, speed, for gravitational potential energy. I also demonstrated that I could continue uphill beyond the energy available from my speed only by swizzling the RipStik. Going uphill requires energy. Crude, primitive, and lacking in measurements, but as a basic demonstrator of the concepts, the RipStik was again useful.

Earlier demonstrations included constant linear motion and accelerated motion.

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