Blocks A and B of masses and rest in contact on a horizontal surface
PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
Blocks A and B of masses mA and mB rest in contact on a horizontal surface. Friction is negligible. A constant horizontal force F directed to the right is applied to block A so that the blocks accelerate together.
(a) Draw separate free-body diagrams for block A and for block B. Label each force with its agent and type.
(b) Treat blocks A and B together as a single system. Draw a free-body diagram for this combined system.
(c) Using your diagrams, explain qualitatively why the contact force that block A exerts on block B does not appear in the diagram drawn in part (b).
(d) Write Newton’s second-law equation for (i) the combined system of part (b) and (ii) block B alone. Solve each equation for the magnitude of the common acceleration. Compare the two results and account for any similarity or difference.