A5.0-m-diameter merry-go-round is initially turning with a 4.0 s period. it slows down and stops in 20 s. what is the angular acceleration as it stops.

First, we can find the initial angular speed of the merry-go-round. Calling the period of revolution, the initial angular speed is


Then, the merry-go-round starts to decelerate, so it is an angular accelerated motion with angular acceleration , and the angular velocity follows the law

We know that after t=20 s, the merry go round stops, so . So we can rewrite the previous equation and solve it to find :


where the negative sign means the merry-go-round is decelerating.

Football was the fourth deadliest sport with a fatality rate of .81 per 100,000 participants. cheerleading, which has been shown to be the most dangerous activity based on injury data, was not included in the study because it was not classified as a sport.this is my answer because it didn’t give me any sports