Question

A rubber ball is tied to a 3-meter string and revolves around an erect pole at a velocity of 7.5 m/s every five (5) seconds. What is the ball’s angular acceleration in radians per square second?

Answer 1

The angular acceleration

$$\beta=a_{\tau}/R=\frac{\Delta v}{\Delta t}/R\\ =\frac{7.5\:\rm m/s}{5\:\rm s}/3\:\rm m=0.5\:\rm rad /s^2$$