Posted by Natasha on .
A grindstone of radius 4.0m is initially spinning with an angular speed of 8.0 rad/s. The angular speed is then increased to 12 rad/s over 4.0s. Assume that the angular acceleration is constant. What is the average angular speed of grindstone?

Physics 
bobpursley,
You have to be kidding.
avg speed= (final+initial)/2