Electric flux through surface of a cube?

In summary, the question asked for the electric flux through the top surface of a 2mx2mx2m cube with a 10nC point charge at its center. Using the equation int(EA) = (Qin)/(ε0), we can find the electric flux by taking the surface area of the top face (4m^2) and dividing the charge (10nC) by the permittivity of free space (8.99x10^-12). This gives a value of 624. Therefore, the electric flux through the top surface of the cube is 624.
  • #1
m84uily
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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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  • #2
You did not find what the question asked. Read the question again.
 
  • #3
The problem asked for the flux. Why are you trying to find the field?
 

FAQ: Electric flux through surface of a cube?

What is electric flux?

Electric flux is a measure of the amount of electric field passing through a given surface. It is represented by the symbol ΦE and is measured in units of volts per meter (V/m).

How is electric flux calculated?

Electric flux is calculated by taking the dot product of the electric field vector and the area vector of the surface. Mathematically, it is represented as ΦE = E * A * cos(θ), where E is the electric field, A is the area of the surface, and θ is the angle between the electric field and the surface.

What is the significance of the electric flux through a surface of a cube?

The electric flux through a surface of a cube can tell us the total amount of electric field passing through that particular surface. This information is useful in understanding the behavior and distribution of electric fields in a given system.

How does the orientation of the surface affect the electric flux?

The orientation of the surface affects the electric flux by changing the angle θ between the electric field and the surface. The larger the angle, the smaller the electric flux will be. This means that the electric flux will be maximum when the surface is perpendicular to the electric field.

Can the electric flux through a surface of a cube be negative?

Yes, the electric flux through a surface of a cube can be negative. This occurs when the electric field and the surface have opposite directions, resulting in a negative dot product. This can happen, for example, when the electric field is pointing into the surface instead of outwards.

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