MCQ
A dancer moves counterclockwise at constant speed around the path shown below. The path is such that the lengths of its segments, $PQ, QR, RS$, and $SP$, are equal. Arcs $QR$ and $SP$ are semicircles. Which of the following best represents the magnitude of the dancer’s acceleration as a function of time $t$ during one trip around the path, beginning at point $P$ ?
  • A


  • C

  • D

Answer

Correct option: B.

b
In the straight sections there is no acceleration, in the circular sections, there is a centripetal acceleration

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