Awind turbine is rotating counterclockwise at 0.5 rev/s and slows to a stop in 10 s. its blades are 20 m in length. (a) what is the angular acceleration of the turbine? (b) what is the centripetal acceleration of the tip of the blades at t=0s? (c) what is the magnitude and direction of the total linear acceleration of the tip of the blades at t=0s?

A law is a proven fact that cannot be changed.

When a hypothesis is tested repeatedly and gives out same results universally, then it becomes a scientific law. The difference between scientific theory is that it gives detailed explanation about how and why things  behave, the way they behave. On the other hand, a scientific law is just a statement that explains the behavior of natural phenomenons. A law is a proven fact that cannot be changed because it becomes law only after multiple times testing of the hypothesis.