A hand pushes two blocks, block A and block B, along a frictionless table through a distance d
A hand pushes two blocks, block A and block B, along a frictionless table through a distance d. The mass of block A is greater than the mass of block B, mA >mB.
(a) Draw a FBD for each block. Does block A do work on block B? If so is the work positive or negative? Does block B do work on block A? If so is the work positive or negative? If each block does work on the other, compare the works in magnitude and sign. Explain your reasoning.
(b) How does the net force on block A compare to the net force on block B? What does your result imply about how the net work done on block A compares to the net work done on block B? Explain.
(c) How do the final kinetic energies of the blocks compare? Use the Work-kinetic energy theorem and your answer to parts (a) and/or (b). Does your answer make sense? Explain.
(d) The initial speed of the two blocks is v0 = 2 m/s to the right. Suppose that the work done on block A by the hand during a given displacement is 10 J. The mass of block A, mA = 4kg, and the mass of block B, mB = 1kg. Calculate the final kinetic energy of each block. Show your work