Force between charges and dielectrics

AI Thread Summary
The discussion centers on calculating the force between two charges placed at positions x=-d and x=d, initially given by the formula q^2/(4*pi*(eps_0)*4*d^2). When a dielectric material with dielectric constant K is inserted between the charges, the question arises whether the force remains unchanged. It is noted that the D field is unaffected by the dielectric, leading to the conclusion that the electric field E remains the same as before. Consequently, the force between the charges is suggested to be the same despite the presence of the dielectric. This raises questions about the influence of dielectrics on electrostatic forces in this specific configuration.
shomey
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suppose I have a charge q at (x=-d) and a charge q at (x=+d).
the force between them is q^2/(4*pi*(eps_0)*4*d^2).

now, I insert a dielectric (K) between (-d/2<x<d/2), and try to calculate the force now...

it seems like it would be the same but it sounds strange...
If I use the D field, it is not effected by the dielectrics, and thus I can see that the electrical field E is the same as before (D/eps_0) and thus the force is the same...

could it be?
 
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shomey said:
suppose I have a charge q at (x=-d) and a charge q at (x=+d).
the force between them is q^2/(4*pi*(eps_0)*4*d^2).

now, I insert a dielectric (K) between (-d/2<x<d/2), and try to calculate the force now...

it seems like it would be the same but it sounds strange...
If I use the D field, it is not effected by the dielectrics, and thus I can see that the electrical field E is the same as before (D/eps_0) and thus the force is the same...

could it be?


someone? please?
i really need help with this...
 

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