Posted by Anonymous on .
When you push a 1.55 kg block resting on a tabletop it takes 1.85 N to start the book sliding. Once it is sliding, however, it takes only 1.5 N to keep the book moving with constant speed. what are the coefficients of static and kinetic friction between the book and the tabletop?

physics 
drwls,
Review the definitions of static and kinetic friction coefficents and the equations will tell you how to proceed.