posted by caroline .
A person pulls with a force of 40 N on two boxes at rest. The top box is 3.0 kg and the bottom box is 6.0 kg. The coefficient of kinetic friction between the floor and the larger box is .20 and the angle is 30 degrees.
a) if the smaller box doesn't slide on top of the larger box, what is the acceleration of the larger box?
b) Given your answer to part a, what must be the minimum value of the coefficient of static friction between the smaller box and the larger box?