A grinding wheel is rotating at 50 rev/s when the power is switched off. It takes 250 s to come to rest. What is the average angular retardation? A wheel of diameter 350 mm rotates with an angular...

A grinding wheel is rotating at 50 rev/s when the power is switched off. It takes 250 s to come to rest. What is the average angular retardation?

A wheel of diameter 350 mm rotates with an angular velocity of 6 rad/s. What is the speed of a point on its circumference?