Find the electrostatic potential above loop of charge Q?

AI Thread Summary
To determine the electrostatic potential at the point (0, 0, D) above a circular wire with charge Q, the relevant approach involves treating the wire as a continuous distribution of point charges. The potential V can be calculated using the formula V = 1/(4πε0)∫dq/r, where r is the distance from the wire to the point of interest, which simplifies to r = √(R² + D²). Since the circular wire is uniformly charged, the contributions from each infinitesimal charge can be integrated, factoring out constants for easier computation. The discussion emphasizes that electrostatic potential is a scalar quantity, negating the need for vector components. Ultimately, the problem was resolved through understanding the integration of the potential from the distributed charge.
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Homework Statement


An electric charge Q is uniformly distributed along a thin circular wire situated in the z = 0 plane at x2 + y2 = R2 . Determine the electrostatic potential at the point (0, 0, D).

Homework Equations

The Attempt at a Solution


I figured the only components that mattered would be the one perpendicular to the wire since the parallel components would cancel with the other side of the wire. But I'm not sure what equation to use, or how to approach this. I also found tan of the angle between the point and the loop is R/D, not sure if I need that?

Thanks in advance.
 
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Keep in mind that electrostatic potential is not a vector quantity. So, there are no components. You'll need to know the formula for the potential of a point charge. Break the circular ring into infinitesimal bits of charge, each bit acts like a point charge.
 
So potential due to a continuous distribution of charge : V= 1/(4πε0)∫dq/r

Where r is the distance of the wire to the point at which you are trying to find the potential. In this case, D.
So since the wire has a radius R. The r=√(R2+D). This is because all points along the ring are at the same distance from the point at (0,0,D).

So then plugging this into the first equation, do you notice anything interesting? Perhaps a constant you can factor out leaving you with an easy integral.
 
Thanks for the help, figured it out now. :)
 
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