forces F1 and F2 acting on a box as the box slides to the
right across a g frictionless floor. If F1 = 2N is horizontal and F2 = 4N is
angled upward by 60o to the floor, the speed of the box v = 3 m/s at a
certain instant.
(a) What is the power due to each force at that instant? Ans. -6 W & 6 W
(b) What is the net power? Ans. zero

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