Potential along the X Axis due to Charge Distribution?

AI Thread Summary
The discussion centers on the electric potential created by a uniformly charged square on the yz plane, specifically examining its behavior along the x-axis. The textbook describes the potential as a bell-shaped curve peaking at x=0, which raises questions about why there is a maximum instead of approaching infinity as x approaches zero. The confusion arises from the difference between point charge potential and the potential from a distributed charge, where the latter requires integrating contributions from all parts of the charge distribution. The correct approach involves calculating the potential from each side of the square and summing them, leading to a finite maximum at the center rather than infinite potential. This clarification highlights the importance of understanding charge distribution when analyzing electric potential.
Joseph Nechleba
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I have a question regarding electric potential and infinity. So,

"A square of side length a with uniformly distributed positive charge lies on the yz plane with its center at the origin. What does the graph of the potential along the x-axis look like?


The answer given in the textbook is a bell-curved-shaped graph with its maximum at x=0. My question is, Why is there a maximum? According to the equation for potential of a point charge, v = k|Q|/(x), shouldn't the potential approach positive infinity as x approaches zero from either direction, as electric potential is a scalar and the charge is uniform?

I am hoping someone can clear my conceptual misunderstanding.
 
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Potential for a point charge is kq/x but the same expression is not true for a charged square. Take a point at a distance x from centre of square along x axis. Now find the potential at that point due to 4 sides of the square. You must know the expression for potential at a point due to a line charge. That times 4 will give total potential because potential is scalar.
 
That makes perfect sense! Thank you for your prompt response!
 
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