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Question 43.
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The electric field on the dashed line in figure 19 -37 vanishes at infinity, but also at two points at a finite distance from the charges.
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So i forgot to put a dashed line here from the image.
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So apologies for that, but doesn't affect the question as a whole.
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Identify the regions in which you can find the electric field to be zero at a finite distance from the charges in region one, to the left of point a, where that negative q charges.
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Region two between point, a and b, three and four, as indicated in the figure.
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So two of these positions, one, two, three, four, two of them have an electric field equals zero at some point in that region.
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So our goal here is to figure out where that would be, right? so we're gonna just separate these regions out, and we wanna see how the electric field contributes at each of these locations.
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So remember if we have a negative charge and two positive charges, the electric field lines, react differently, so they leave, you think it as leaving the positive charge and entering the negative charge.
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So if we look at the electric field lines at each of these regions, we note that for region one, again, to the left of charge negative q, the negative sign contributes to the right -hand direction, and the two positive charges contribute to the left.
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But no, because there's the strength of the negative charge is much higher than the other two, because it is closer...