Physics
A block of mass 30 kg is pulled up a slope (diagram below) with a constant speed by applying a force of 200 N parallel to the slope. A and B are the initial and final positions of the block. Calculate the force of friction offered by the surface AB.
Force
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Answer
Given, mass of block (m) = 30 kg
Force applied (F) = 200 N
Work done along AB :
WAB = F x SAB
= 200 x 3 = 600 N m = 600 J
Work done along CB:
WCB = m x g x SCB
= 30 x 10 x 1.5 = 450 J
Let, friction force = f
Work done by friction WF =f x 3
Hence, the force of friction offered by the surface AB is 50 N.
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