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Question
A block of mass 20 kg is pulled up a slope (fig.12) with a constant speed by applying a force of 500 N parallel to the slope. A and B are initial and final positions of the block.
(a) Calculate the work done by the force in moving the block from A and B.
(b) Calculate the potential energy gained by the block.
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Solution
(a) given force = 500N
Vertical displacement = Final position - initial position = BC = 4m
work done = force x displacement = 500 x 4 = 2000J
(b) P.E gained = mgh = (mg) h = 500 x 4 = 2000J
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A block of mass 30 kg is pulled up a slope, as shown in diagram with a constant speed, by applying a force of 200 N parallel to slope.
A and B are initial and final positions of block.
(i) Calculate the work done by force in moving the block from A to B.
(ii) Calculate P.E. gained by block. [g=10ms-2]
