Which activity best exemplifies angular motion?

• A. A gymnast twirling through the air
• B. A sprinter running down the track
• C. A roller coaster car moving in a straight line
• D. A cyclist riding uphill in a straight line

Answer: (A)

Angular motion is rotation around an axis. A gymnast twirling through the air demonstrates this best because the body is rotating about a central axis, changing its orientation as parts move around that axis. The other activities involve translating along a path: a sprinter runs straight, a roller-coaster car moves in a straight line, and a cyclist riding uphill in a straight line—none of these track rotation about an axis in the same way a spin does. So the gymnast’s spin is the clear example of angular motion.