A block of stone of 40 kg is hauled along a horizontal floor by a force inclined 20 degrees to the horizontal. If the coefficient of friction between the stone and the floor is 0.3, determine the effort required to just move the stone from rest.
A. 157.77 N
B. 140.63 N
C. 117.72 N
D. 112.9 N
E. 84.2 N
Answer: D
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Power Engineering
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