I. Applying Newton\'s laws to interacting objects moving uniformly In the diagra
ID: 1774293 • Letter: I
Question
I. Applying Newton's laws to interacting objects moving uniformly In the diagram below, three identical bricks are pushed across a level floor at constant speed by a horizontal force exerted by someone's hand. There is friction between the blocks and the floor. The stack of two bricks is system A, and the single brick is system B. Constant speed A. Is the magnitude of the net farce on B greater than, equal to, or less than the magnitude of net on A? Explain carefully how you . the force know B. Is the direction of the net force B the as the direction of an , or on same the net force A does it point in the opposite direction? Explain carefully how you know, C. In the boxes below, draw separate free body diagrams for A and B. You must give each force label a subscript indicating the object exerting the force and the object on which the force is exerted, eg, n Aon R, Fitoun, FGLEoat, fia on . D. Is the magnitude of the force exerted on A by B greater than, equal to, or less that the magnitude of the force exerted on B by A? Cxplain carefully how you know Would your answer change if the hand were pushing the blocks leftward at constant speed rather than rightward? If so, how? If not, why not? E. Identify all Newton's third law (action-reaction) force pairs among the forces in your two free-body diagrams by placing one or more small "X symbols through each member of the pair (mark each member of the first pair with X, each member of the second pair with XX, etc.) what criteria did you use to identify the force pair(s)? Is your answer to part D consistent with your identification of action-reaction force pairs? If so, explain how. If not, change your answer to make it consistent. F. Rank the magnitudes of all the horizontal forces on your two free body diagrams, remembering that the speed is constant.Explanation / Answer
A. As the bricks are moving with constant speeds, net force on each brick is zero. Thus, magnitude of net force on B is equal to magnitude of net force on A.
B. As the net force is zero. So, the direction is same for both A and B.