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Newton's third law and free-body diagrams

AP.PHYS: INT‑3.A (EU), INT‑3.A.3 (EK), INT‑3.A.3.1 (LO), INT‑3.A.3.2 (LO), INT‑3.A.3.3 (LO), INT‑3.A.4 (EK), INT‑3.A.4.1 (LO), INT‑3.A.4.2 (LO)


Two boxes of equal mass are pulled along a rough floor by the force F shown in the figure below. The boxes have a resulting acceleration of 2, point, 5, start text, m, slash, s, end text, squared to the right.
Two rectangles of the same size sit on a flat horizontal line. A line connects rectangle A, on the left, to rectangle B, on the right. An arrow from rectangle B points to the right and is labeled with the letter F.
Which of the following statements correctly compares the forces box A and B exert on one another?
Choose 1 answer: