Determine the work as objects moves in straight line

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SUMMARY

The discussion focuses on calculating the work done by a force represented as F = axi + byj, with specific values a = 2.9 N/m and b = 3.9 N/m, as an object moves from the origin to the point r = (10.0i + 21.5j). The initial attempt to calculate work using W = FΔx resulted in an incorrect value of 2675 J. The correct approach involves using the integral definition of work, leading to the evaluation of W = ∫(0,0(10,21.5) (ax i + by j) · (dx i + dy j), which simplifies to W = (a/2) x²|₀¹₀ + (b/2) y²|₀²₁.₅, yielding an approximate result of 1000 J.

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Homework Statement


Assume that a force acting on an object is given by F=axi+byj, where a=2.9 N/m and b=3.9 N/m. Determine the work done on the object by this force as it moves in a straight line from the origin to r=(10.0i +21.5j)

The Attempt at a Solution


i used the given info to calculate the magnitude of the Force. F=2.9(10)+3.9(21.5)=112.9. i then calculated the distance traveled by doing arctan (21.5/10)=23.7. W=FΔx, W=112.9x23.7=2675. which is wrong, apparently the answer is roughly 1000 J.
 
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Maybe you should try calculating the work directly from the definition:

W = ∫(0,0(10,21.5) (ax i + by j). (dx i + dy j)

=∫010 ax dx + ∫021.5 by dy

= (a/2) x2|010 + (b/2) y2|021,5

Complete the evaluation and see how that works out for you.
 

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