Question

part a

a girl and a boy are riding on a merry-go-round that is turning at a constant rate. the girl is near the outer edge, and the boy is closer to the center. who has greater angular displacement?

both the girl and the boy have the same nonzero angular displacement.
the boy has greater angular displacement.
the girl has greater angular displacement.
both the girl and the boy have zero angular displacement.

Explanation:

Analyze rigid body rotation

Using the Rotational Kinematics knowledge point

$$ \Delta \theta_{\text{girl}} = \Delta \theta_{\text{boy}} eq 0 $$

Every point on a rotating rigid body sweeps out the same angle in any given time interval. Since both riders are on the same merry-go-round, they rotate together through the exact same angular displacement.

Answer:

• Both the girl and the boy have the same nonzero angular displacement. (Correct answer)
• The boy has greater angular displacement.
• The girl has greater angular displacement.
• Both the girl and the boy have zero angular displacement.