Calculating Electric Field in Water-Filled Container: What is the Best Method?

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To calculate the electric field generated by a charge above a water-filled container, it's essential to consider the different electrostatic constants for air and water. The method of images is commonly referenced in textbooks for such scenarios, treating the water surface as an infinite plane. However, some participants question whether this method is applicable since it typically assumes a grounded perfect conductor. An alternative approach using Gauss' Law and Cartesian coordinates may also be viable, though it requires careful trigonometric adjustments for the water's surface. Overall, both methods have their merits depending on the specific conditions of the problem.
LuGoBi
This is killing me. I have an electrical charge in the air and below it I have a container filled with water. How do I calculate the electric field generated by the charge on the bottom of the cointainer? Bear in mind the electrostatic constant in water is different than from air.
 
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Assuming the surface of the water is like an infinite plane, this is a standard image problem treated in most textbooks.
 
pam said:
Assuming the surface of the water is like an infinite plane, this is a standard image problem treated in most textbooks.

Could you ellaborate, then?
 
I can't go through the whole method of images.
You may have to look at a book.
 
smells like homework?
 
Excuses me, pam (or others), but doesn't the method of images require that the boundary region be a (grounded) perfect conductor?

Treating the problem in a brute-force manner (Gauss' Law, Cartesian coordinates), this doesn't sound TOO bad. You just need to invoke some pretty clever trigonometry to account for the surface of the water.
 
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