Meriam, Kraige & Bolton — Kinematics of Particles: Problem 2_106

2/106 The sprinter begins from rest at position \( A \) and accelerates along the track. If the stationary tracking camera at \( O \) is rotating counterclockwise at the rate of \( 12.5 \text{ deg/s} \) when the sprinter passes the \( 60\text{-m} \) mark, determine the speed \( v \) of the sprinter and the value of \( \dot{r} \).