Calculus 3: Work Homework: Electric Dipole Field

tarantino5
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Homework Statement



An electric dipole with dipole moment p = 4 × 10−5 C-m sets up
an electric field (in Newtons per coulomb)

F(x,y,z) = kp/r^5 <3xz, 3yz, 2z^{2} - x^{2} - y^{2}>

where r = (x^{2} + y^{2} + z^{2})^{1/2} with distance in meters and k = 8.99 ×
109 N-m^{2}/C^{2}. Calculate the work against F required to move a particle
of charge q = 0.01 C from (1,−5, 0) to (3, 4, 4). Note: The force on
q is qF Newtons.

Homework Equations



∫^{b}_{a} F(c(t)) * c'(t) dt

The Attempt at a Solution



I know that I need to set ∇f = F and find a potential function. I'm not sure what the parametric equation should be.
 
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tarantino5 said:
I know that I need to set ∇f = F and find a potential function. I'm not sure what the parametric equation should be.

Perhaps you don't need to calculate the potential at all. Seems like you get work directly from the force, according to your formula.

The path parametrization depends on the path of course. It seems a path is not specified in the problem. Why is it not needed to solve the problem?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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