# point charge and electric flux

by channel1
Tags: charge, electric, flux, point
 P: 74 1. The problem statement, all variables and given/known data You measure an electric field E at a distance x from a point charge. What is the electric flux through a sphere whose center is at that distance and whose radius is less than x from the charge? 2. Relevant equations E*dA = (q_enc)/(e_0) 3. The attempt at a solution I'm not sure that I'm understanding the question....The sphere does not enclose the point charge since its center is at x and its radius is less than x from the charge, so doesn't that mean q_enc = 0 and the flux is 0? (I have the answer so I know it's not zero, but I don't understand what I'm missing conceptually here....)
 P: 1,135 net flux is 0 it means the new electric field lines crossing the total surface is 0 look at pic ... all field lines entering exit the Gaussian surface !! so net field through surface is 0 Attached Thumbnails
Mentor
P: 11,958
 Quote by channel1 3. The attempt at a solution I'm not sure that I'm understanding the question....The sphere does not enclose the point charge since its center is at x and its radius is less than x from the charge, so doesn't that mean q_enc = 0 and the flux is 0?
I believe that is correct.
 (I have the answer so I know it's not zero, but I don't understand what I'm missing conceptually here....)
That's weird, what is the "correct" answer that you have been given?

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