Solve Gauss's Law and Flux: 55.3M Excess Electrons

AI Thread Summary
The discussion centers on calculating the net electric flux through a closed surface containing 55.3 million excess electrons. The key equation used is Φ = Qin/ε, where Qin represents the enclosed charge and ε is the permittivity constant (8.85 x 10^-12 F/m). Participants clarify that the excess electrons indicate a negative charge, which should be considered in the calculation of Qin. The solution involves multiplying the number of excess electrons by the elementary charge (-1.60 x 10^-19 C) to find Qin. The problem is ultimately resolved by applying the correct formula, demonstrating that the solution can be simpler than initially perceived.
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[SOLVED] Gauss's Law and Flux

ok so i have the biggest question of all i tried solving the following problem:

55.3 million excess electrons are inside a closed surface. What is the net electric flux through the surface?

now i tried the following equations:

\Phi= E . A = Qin/\epsilon

but i have the biggest question when there is excess electron does it mean that the electron field is negative, and if it does then that goes in Qin where then \Phi would be equal to Qin/\epsilon, and epsilon being 8.85*10 (permittivity constant)

well any help in solving this problem is very grateful
 
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You can solve for the enclosed charge, since the elementary charge of an electron (-1.60*10^-19 C) and the number of electrons is known. Just use Q/epsilon to solve for flux.
 
oh wow that was easy, i always see things harder then they are, thanks terbum
 
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