Purpose: To demonstrate the idea of energy due to position and also the idea of centripetal force.

Cenco Loop the Loop apparatus with various balls.

Find the spot on the loop-the-loop track where the clear plastic ball will just make it around the loop. Now place the steel ball at the same spot and see that it also just makes it around. If the steel ball is moved any lower it won't make it around (thus demonstrating that the energy needed to traverse the loop depends only on the initial height and not on the mass of the balls). Now place the black plastic ball of diameter 4.3 cm so that it just traverses the loop-the-loop. Then try it with the clear plastic and steel balls at the same spot. These do not make it because their centers of mass are lower and they do not have enough energy.

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