STEP 1 - FBD: Draw a SINGLE free body diagram (FBD) of the system including Block A, Block B and the cable. From this, determine which forces do work on this system.
STEP 2 - Kinetics: Write down the work/energy equation. Determine the work done by the forces that you identified above in STEP 1.
STEP 3 - Kinematics: Review the constrained motion kinematics from Section 1.D of the course lecture book. To this end, you will write down an expression for the length of the cable in terms of sA, sB and constants. Differentiate this expression to relate the speeds of A and B.
STEP 4 - Solve
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