The coefficient of static friction between block A and a horizontal floor is 0.53 and the coefficient of static friction between block B and the floor is 0.40. The mass of each block is 1.3 kg and they are connected together by a cord.
(a) If a horizontal force pulling on block B is slowly increased, in a direction parallel to the connecting cord, until it is barely enough to make the two blocks start moving, what is the magnitude of at the instant that they start to slide?
(b) What is the tension in the cord connecting blocks A and B at that same instant?