Use the values RE = 6370 km = 3960 mi for the radius of the earthTo determine the coeffici...

Use the values RE = 6370 km = 3960 mi for the radius of the earth

To determine the coefficient of static friction between two materials, an engineer at the U.S. National institute of Standards and Technology places a small sample, of one material on a horizontal disk whose surface is made of the other material and then rotates the disk from rest with a constant angular acceleration of 0.4 rad/s2. If she determines that the small sample slips on the disk after 9.903 s, what is the coefficient of friction?