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Hello everyone.
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In this problem, we're asked to find the force exerted on a chloride ion by a water molecule that is pointing along its axis of electric dipole moment.
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So here's the situation.
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We have a water molecule whose dipole moment is oriented in the positive x direction.
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So we've got that the negative charge is to the left and the positive charges to the right.
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And so we choose the right -hand direction to be the positive x direction.
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And along this direction, along this line, the words the positive x -axis, some distance of three nanometers away, we place the chloride ion, which is the negatively charged particle with a charge of minus 1 .6 times 10 .3 minus 19 kulams.
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We're also told that we can assume that the separation between the chloride ion and the water molecule is much, much greater.
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Than the separation between the charges of the dipole itself.
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So let's use this approximation for the dipole, for the electric field of the dipole, which is approximately the dipole moment divided by 2 pi epsilon not times the separation to the point of interest cubed.
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And since we're asked to find the electric force, we also know that the force is going to be equal to the electric field times the charge of the particle whose force, we're interested in finding...