Question
You push a box up a ramp using a horizontal 100-N force F, For each 5 m of distance a long the ramp the box gain 3 m of height. Find the work done by F for each 5 m it moves along the ramp by directly compulling the dot product uct of the magnitudes of F and s with the cosine of the angle between their directions, by finding F,(the component of the force in the direction of the displacement) and multiplying it by the magnitude of the displacement, and by finding component of the displacement in the direction of the force and multiplying it by the magnitude of the force.
Explanation / Answer
a)
F = 100 i
S = 4 i + 3 j
W = F.S = (100 i) . (4 i + 3 j) = 400 J
b)
work done = 100*cos(theta)*5 = 100* 4/5*5 = 400 J
c)
Fs = 100*(cos(theta)) = 400/5
W = (400/5)*5 = 400 J
d)
Sf = 5*4/5 = 4
W = 100*4 = 400 J