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Question 4.30: An electric dipole p, pointing in the y direction, is placed...

An electric dipole p, pointing in the y direction, is placed midway between two large conducting plates, as shown in Fig. 4.33. Each plate makes a small angle θ with respect to the x axis, and they are maintained at potentials ±V . What is the direction of the net force on p? (There’s nothing to calculate, here, but do explain your answer qualitatively.) 

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Net force is to the right (see diagram). Note that the field lines must bulge to the right, as shown, because E is perpendicular to the surface of each conductor.

4.30

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