Force on a sphere in a constant external electric field

AI Thread Summary
An uncharged solid sphere placed in a constant external electric field E0 experiences induced charge separation, resulting in the formation of a dipole. The force on the sphere can be calculated using the induced charge and the electric field near the sphere. The equation F = q*E is applicable, where q represents the induced charge and E is the electric field acting on the sphere. The discussion highlights the importance of recognizing that while the external field is uniform, the induced dipole creates a net force on the sphere. Understanding these concepts is crucial for solving the problem effectively.
captain.joco
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Homework Statement


An uncharged solid sphere is paced in a constant external electric field E0. What is the force on the sphere?


Homework Equations





The Attempt at a Solution


I know ( already have found ) the electric potential and electric field around the sphere. Also worked out the surface charged density. I don't know how to calculate the force..Any help please?
 
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Isn't F = q*E ?
 
It seemed too simple somehow... Is q the induced charge on the sphere, and E the electric field close to the sphere??

Thank you for your help
 
captain.joco said:
It seemed too simple somehow... Is q the induced charge on the sphere, and E the electric field close to the sphere??

Thank you for your help

If there is charge separation, what will the net force be?
 
Got it! Thanks a lot for the help!
 
This is the exact question i was looking for help with and still not sure of what the next step is.

I know the uniform E-field causes the sphere to gain an induced dipole. From this how do you get the force? Is it ok to just assume the E-field remains uniform.. this can't be right as there would then be no force and seems there must be a force from the way the question is worded.
 
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