When you push a 1.82-{\rm kg} book resting on a tabletop, it takes 2.21 N to start the book sliding. Once it is sliding, however, it takes only 1.52 N to keep the book moving with constant speed.

Question

When you push a 1.82-{\rm kg} book resting on a tabletop, it takes 2.21 N to start the book sliding. Once it is sliding, however, it takes only 1.52 N to keep the book moving with constant speed.
1-What is the coefficient of static friction between the book and the tabletop? 
2-What is the coefficient of kinetic friction between the book and the tabletop?

bobpursley · Answer

forcefriction=pushing force when.. mu*mg=2.21 solve for mu, then do it again for kinetic coefficent.