I have a question about electric flux.(adsbygoogle = window.adsbygoogle || []).push({});

Intuitively it makes that if a charge is outside a closed object, then the net flux inside that object will be zero..but once I write it down on paper it loses its sense.

I attached a picture for clarification.

Flux is equal to the field, times Area.

Flux = E*A

So, let's say we have a point charge on the side of a cylinder. For argument's sake, let's say on the axis of the cylinder.

For the flux to be zero, the flux entering on one side has to be equal to the flux exiting on the other side.

Now the problem with this in my mind, is that for the flux to be the same on both sides of the cylinder, both the field and the area must stay constant because of E*A.

Now, the area stays constant obviously...but the field drops off by an inverse square of the distance so it will have a lesser magnitude.

If the field changes....how in the world could the flux be zero?

I hope I explained my question decently...the picture should help.

Thank you anybody.

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# Homework Help: Gauss's Law Theory Question

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