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A point charge +Q is fixed at point A. The electric flux through the inclined (lateral) surface of a cone is 3Q/(5*e0), where e0 is the permittivity of free space. A charge -Q is now also placed at point B (at the apex of the cone, such that by symmetry the flux from -Q through the same surface is -2Q/(5*e0)). If the net electric flux through the inclined surface is n*Q/(5*e0), find the value of n.
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Correct answer: 1
Solution
By superposition, net flux = flux from +Q + flux from -Q = 3Q/(5e0) + (-2Q/(5e0)) = Q/(5e0), giving n = 1.
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