In a familiar demonstration, a hoop and a solid disk of the same diameter and mass are started from rest at the top of an inclined plane and race to the bottom. The disk reaches the bottom with a larger speed than the hoop and arrives first. Why?

1.
S.
Lin
et al, “
Simple model of a rolling water-filled bottle on an inclined ramp
,”
Phys. Teach.
53
,
548
549
(Dec.
2015
).
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