Intergal? work done by a non constant force

AI Thread Summary
To calculate the work done by a non-constant force acting on an object moving in the x-direction, the relevant equation is W = ∫ F · d x. The force is given as F = (4.38 x i + 2.84 y j) N, but since the movement is only along the x-axis, only the x-component contributes to the work. The integration simplifies to W = ∫ from 0 to 5.52 of 4.38x d x. The solution involves integrating the x-component of the force over the specified distance.
Chuck 86
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Homework Statement


A force F = (4.38 x i + 2.84 y j) N acts on an object as it moves in the x direction from the origin to x = 5.52 m. Calculate the work done on the object by the force.


Homework Equations


intergal of F from 0 to 5.52m

The Attempt at a Solution



not sure if I am suppose to intergrate, or what I am supposed to do to start the process
 
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W=\int\limits_{x=0}^{x=5.52}\vec{F}.{\rm d}\vec{x}

where \vec{x}=x\vec{i} is the position vector.
 
ok so u intergrate the sum of X and Y right?
 
Not exactly. By the looks of the problem, the object only moved in the x direction. So there is no net work in the y-direction. You only integrate the x-component.
 
So then it would be the intergal of 4x?
 
Yes.

{\rm d}\vec{x}={\rm d}x \vec{i}

so

\vec{F}.{\rm d}\vec{x}=\left(4.38x \vec{i}+2.84y \vec{j}\right). \vec{i} {\rm d}x=4.38x{\rm d}x

W=\int\limits_0^{5.52} 4.38x{\rm d}x
 
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