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mybrohshi5
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Homework Statement
A horizontal 25 N pushing force acts on a 10 kg crate moving up a ramp. The ramp is inclined at 37 degrees above the horizontal.
How much work is done by this force in moving the crate a distance of 15m along the ramp?
Homework Equations
W = Fd
The Attempt at a Solution
This was on a previous test i took and i got it wrong and now looking over it again i cannot seem to figure it out.
I thought i could take the component of the pushing force parallel to the ramp and subtract the component of the weight of the block that is parallel to the ramp then just multiply that by the distance but that didnt work out to well.
here is was i did
The component of the pushing force parallel to the ramp is
25cos(37) = 19.96
the component of the weight parallel to the ramp (and opposite in direction of the component of the pushing force parallel to the ramp) is
mgsin(37)
10(9.8m/s^2)sin(37) = 58.9
so subtract those two
19.9 - 58.9 = - 39N
so W = 39N(15m)
W = 585 J
the correct answer is 300 J
Any help would be great.
Thank you :)