A force acting on a particle moving in the xy plane is given by

AI Thread Summary
The discussion revolves around calculating the work done by a force acting on a particle moving in the xy plane, defined by the equation F = 2y i + x² j. Participants emphasize the need to analyze the force in terms of its components along the x and y axes, noting that the force is not constant and varies with the particle's position. They suggest evaluating the work done along specific paths, particularly from points O to A and A to C, while considering the direction of the force and its components. The conversation highlights the importance of understanding vector notation and the application of dot and cross products in solving the problem. Ultimately, the goal is to compute the work done as the particle moves along the defined paths.
AryRezvani
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Homework Statement



2yoe5gx.jpg


Homework Equations



W=∫ Fx dx

The Attempt at a Solution



I think you got to split this one in terms of axis.

∫(2yi + x2j) dx

Pretty lost on it.
 
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Well, they do not say in which direction the vectors i and j point, so let us assume that vector i is parallel to the x-axis and vector j is parallel to the y-axis, which is the usual convention.

To start you off,
Path OAC:
From O to A, can you find the force on the particle along this path knowing that y = 0. In what direction does the force point from the equation given for force.? Does the force do any work along this path? Note that the particle is moving along the x-axis which is what vector direction, i or j. Can you find an equation for the path of the particle in terms of vectors i oj or both?

from A to C, same questions.

You might want to review dot and cross product as that that is what this problem seems to be designed for.

PS. Your picture shows up a bit large.
 
Understood, so quick question, is the blue line the force? Then the other lines simply components of the force?

Still a little lost. We want to calculate the work required to mvoe the object to the right first. Force is constant right? So would you use fΔrCosθ?
 
AryRezvani said:
Understood, so quick question, is the blue line the force? Then the other lines simply components of the force?

Still a little lost. We want to calculate the work required to move the object to the right first. Force is constant right? So would you use fΔrCosθ?
No, the force is not along the blue line.

No, the force is not constant.

The force depends upon the location of the particle according to \displaystyle \vec{F}=2y\hat{\text{i}}+x^2\hat{\text{j}}\ .

You are to calculate the work done by that force in moving the particle from point, O, to point, C, along each of the colored paths.
 
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