Two balls doing the loop: Testing Experiment

Aim

Make a prediction about whether the balls will make it around the loop. Revise your assumptions about the system if the prediction does not work out as you predicted.

Prior Knowledge

• Conservation of energy
• Newton's laws
• Rotational Motion

Description of the Experiment

Watch the first video where a solid wooden ball is rolled from a certain height.

Once you have watched it, what do you predict should happen (based on your knowledge of Newton's laws, rotational motion and energy conservation) if a smaller rubber mouse ball is released from the same height

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	Frame rate: 30fps Size: 480 X 360 File Size: 0.15Mb
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Questions

• Did your prediction match the outcome of the second experiment?
• If not, try and think what assumptions you made about the system. Make a list of all the assumptions you made.
• Could overlooking any of the assumptions explain what you saw in the second experiment? Use hypothetico deductive reasoning to check each assumption in turn. It may help to rerun both videos to check your reasoning.