Electric flux through surface of a cube?

AI Thread Summary
The discussion centers on calculating the electric flux through the top surface of a cube with a point charge at its center. The user attempts to apply the equation for electric flux, integrating the electric field over the surface area. However, they mistakenly focus on finding the electric field instead of directly calculating the flux. The correct approach involves using the total charge and permittivity of free space to determine the flux through the entire surface and then dividing by six for the top surface. The user is advised to clarify their focus on calculating flux rather than the electric field.
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Homework Statement


A 10nC point charge is at the center of a 2mx2mx2m. What is the electric flux through the top surface of the cube?


Homework Equations



int(EA) = (Qin)/(ε0)

The Attempt at a Solution



int(EA) = EA + EA + EA + EA + EA + EA = 6EA

A = 4m^2

Qin = 10nC

ε0 = 8.99x10^-12

6EA = (10x10^-9)/(8.99x10^-12)

E = (10x10^-9)/((8.99x10^-12)(6)(A))

E = (10x10^-9)/((8.99x10^-12)(6)(4))

E = 3745

Then for just the top surface

Etop = 3745/6 = 624

Where did I go wrong this time? XD Thanks in advance!
 
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You did not find what the question asked. Read the question again.
 
The problem asked for the flux. Why are you trying to find the field?
 
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