Forces and Blocks, Part II

Newton's 2nd & 3rd Laws

II. Varying speed
The three identical bricks from part I now are pushed with the same force by the arrow as in part 1, but but across a different table that has a smaller coefficient of friction.

A. Describe the motions of Systems A and B.

 

B. Compare the net force (magnitude and direction) on system A to that on system B. Explain your reasoning.

 

C. Draw and label separate free body diagrams for systems A and B.

D. Rank the magnitudes of all the horizontal forces that appear in your free body diagrams in order from largest to smallest as far as you can. Explain your reasoning. (Describe explicity how you used Newton's 2nd and 3rd laws in your ranking of the horizontal forces).

Is it possible to completely rank the horizontal forces in this case?