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# Understanding electric flux watch

1. I'm struggling with the question below and therefore don't have a proper understanding of electrostatic etc.

Here is the question that's troubling me, and any guidance (starting from fundamentals!) would be much appreciated:

A point charge is at a distance from a square surface of side d. The charge is directly above the centre of the square.
Find the flux through the square.

Could I also confirm whether my physical interpretation of electric flux of correct:
I visualise flux, , as the amount of passing through a surface, S, in space. Equivalently one can say:

...is this the correct interpretation?

2. (Original post by Sm0key)
I'm struggling with the question below and therefore don't have a proper understanding of electrostatic etc.

Here is the question that's troubling me, and any guidance (starting from fundamentals!) would be much appreciated:

A point charge is at a distance from a square surface of side d. The charge is directly above the centre of the square.
Find the flux through the square.

Could I also confirm whether my physical interpretation of electric flux of correct:
I visualise flux, , as the amount of passing through a surface, S, in space. Equivalently one can say:

...is this the correct interpretation?

yeah if you did A level physics it's a simple and familiar idea being presented in an unfamiliar notation.

in this case it might help to imagine the point source is enclosed inside an imaginary cube and you're only interested in the flux going through one side - since the flux through a closed surface containing a charge is Q/ε0 it can be looked at as a geometry question really.
3. (Original post by Joinedup)
yeah if you did A level physics it's a simple and familiar idea being presented in an unfamiliar notation.

in this case it might help to imagine the point source is enclosed inside an imaginary cube and you're only interested in the flux going through one side - since the flux through a closed surface containing a charge is Q/ε0 it can be looked at as a geometry question really.
Oh ok great thanks.

So to confirm then: by using a cube of edge d the radial symmetry of the flux over this closed area means that the answer is ?
4. (Original post by Sm0key)
Oh ok great thanks.

So to confirm then: by using a cube of edge d the radial symmetry of the flux over this closed area means that the answer is ?
That's what I got

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