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Chuck 86
Oct8-09, 10:39 AM
1. The problem statement, all variables and given/known data
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.


2. Relevant equations
intergal of F from 0 to 5.52m

3. The attempt at a solution

not sure if im suppose to intergrate, or what im supposed to do to start the process

Donaldos
Oct8-09, 11:18 AM
W=\int\limits_{x=0}^{x=5.52}\vec{F}.{\rm d}\vec{x}

where \vec{x}=x\vec{i} is the position vector.

Chuck 86
Oct8-09, 02:33 PM
ok so u intergrate the sum of X and Y right?

Gear300
Oct8-09, 02:49 PM
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.

Chuck 86
Oct8-09, 03:04 PM
So then it would be the intergal of 4x?

Donaldos
Oct8-09, 03:12 PM
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