Assignment:
Block A in the figure weighs w1 and block B weighs w1. The coefficient of kinetic friction between all surfaces is uk.
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1. Find the magnitude of the horizontal force necessary to drag block B to the left at constant speed if A rests on B and moves with it (figure (a)).
2. Find the magnitude of the horizontal force necessary to drag block B to the left at constant speed if A is held at rest (figure (b)).