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Experiment with the interactivity and make your own conjecture about the locus of $P$.
As the small circle moves, points on the small circle come into contact with points on the big circle. Think about the lengths of the arcs on the two circles that are made up of the points that have come into contact.
Just Rolling Round
Age 14 to 16
Challenge Level 
Experiment with the interactivity and make your own conjecture about the locus of $P$.
As the small circle moves, points on the small circle come into contact with points on the big circle. Think about the lengths of the arcs on the two circles that are made up of the points that have come into contact.
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