Potential along the X Axis due to Charge Distribution?

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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!