My problem has force decreasing with(adsbygoogle = window.adsbygoogle || []).push({}); F=(1/r^2)r, where F is a vecotr andris unit vector. i need to find a).work done in moving from a point at r=sqrt(2) to a point at r=2*sqrt(2) by a direct radial path and (b) by a path from (1,1)-->(2,1)-->(2,2). Compare my answers.

a)I did direct radial path using Work=Integral[1/r^2] from sqrt(2) to 2*sqrt(2). I got sqrt(2)/2.

b) This where problem is: from (1,1)-->(2,1) x:1-->2, y=1, dl=dxx, so i get F (dot) dl = (x^2+y^2)^2, however, I am not sure I am setting up the x and y components correctly. from (2,1)-->(2,2) y:1-->2, x=2 dl=dyyand again same issues of x and y components.

i did read that r vector=sin(theta)cos(phi)x+sin(theta)sin(phi)y, but was not sure how to incorparate this into line integral part of problem.

any help would be appreciated, thanks

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# Homework Help: E&M line integral setup

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