Electric field magnitude at large distances

AI Thread Summary
The electric field magnitude at large distances from an electric dipole decreases as approximately 1/r^3 due to the geometry of electric field lines spreading over a larger area. To understand this, one can start by mathematically modeling a dipole configuration and calculating the electric field at varying distances. As the distance increases, the field strength diminishes more rapidly than it does for a point charge, leading to the 1/r^3 relationship. This behavior can be explained through the mathematics of dipole fields, which reveal how the field lines behave at significant distances. A deeper understanding of the underlying math will clarify the reasons for this rapid decline in electric field strength.
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I have a question which basically asks me to show and explain why electric field magnitude a very large distance r from an electric dipole falls away as approximately 1/r^3.

Can anyone point me in the right direction of thinking?

Could it be because the electric field lines are spread out more rapidly over a larger area of space?

Thanks
 
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You could start off by doing mathematically, setting up a dipole configuration and taking the electric field at a point r not so far away.

Then take it to be VERY far away...and you should be able to see how it boils down to 1/r^3.

Now as to an actual explanation as to why this happens...try to dig in and understand how the mathematics explain what is going on.
 
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