Concept explainers
If you put a penny on the center of a rotating turntable, it does not slip. However, if you place the penny near the edge, it is likely to slip off. Which answer below explains this observation?
a. The penny moves faster at the edge and hence needs a greater force to keep it moving.
b. The edge is more slippery since the grooves are farther apart.
c. The radial acceleration is greater at the edge and the friction force is not enough to keep the penny in place.
d. The outward force responsible for slipping is greater at the edge than at the middle.
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