Calculating Forces on Two Charges Above a Conducting Sheet

AI Thread Summary
The discussion focuses on calculating the forces acting on two charges, +Q and -Q, positioned above a conducting sheet. The user attempted to solve the problem using the method of image charges, resulting in a complex expression for the force. They expressed difficulty in finding the modulus of the vector and writing it in components due to the complexity of their derived formula. Another participant confirmed that the user's answer appears to consist of vector components. The conversation highlights the challenges of applying image charge techniques in electrostatics.
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Homework Statement



Two charges +Q and -Q are a horizontal distance a apart and a vertical distance b above a large conducting sheet. Find the components of the forces acting on each charge.

Homework Equations





The Attempt at a Solution



Ok well I've tried to solve this using image charges (i.e. positing 2 imaginary charges below the plate) and have got an expression for F. My problem is that the expression is really horrible so i can't find the modulus of the vector bit and thus write it in components.. have i gone wrong?

my answer is F = kQ^2 times vector ( [1/a^2 - a/(a^2 + 4b^2)^3/2] , 0 , [2b/(a^2 + 4b^2)^3/2 - 1/4b^2] )

Thanks!
 
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Those look like vector components from where I'm sitting! :smile:
 
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