1. The problem statement, all variables and given/known data How come for the following image when I assume block B slips up, block A does not move. The free body diagram at block B does not have a normal from the ground. This is a static friction problem. 2. Relevant equations No relevant equations all theory 3. The attempt at a solution This should be the Free body diagram but why does B have no normal from the ground when this assumption is made?