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 10 rad/s over the next 4.0 seconds. Assume that the angular acceleration is constant.
A. What is the average angular speed of the grindstone?
B. What is the magnitude of the angular acceleration of the grindstone?
C. Through how many revolutions does the grindstone turn during the 4.0-second interval?