SOLUTION: Find the work done by the force F in moving an object from P to Q. F=-4i + 20j P(0,10) Q(5,25)

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Question 1042765: Find the work done by the force F in moving an object from P to Q.
F=-4i + 20j P(0,10) Q(5,25)

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Force Vector
F = -4i + 20j
F = < -4, 20 >


Displacement Vector
D = < Qx - Px, Qy - Py >
D = < 25-10, 5-0 >
D = < 15, 5 >


Work Done
W = F dot D
W = < -4,20 > dot < 15,5 >
W = -4*15 + 20*5
W = -60 + 100
W = 40

Note: if the force is in newtons and the displacement is in meters, then the work done is in joules.