Electric force (varying) on q from Q (conceptual question)

AI Thread Summary
The discussion revolves around calculating the electric force acting on a charge q from a fixed charge Q, with q positioned on the y-axis. The user inquires whether integrating the electric force formula can determine the force required to move q a distance "a" along the y-axis. It is clarified that while the force varies according to Coulomb's law, integrating with respect to distance will yield the work done by the force, not the force itself. The importance of understanding that the area under the force versus distance graph represents work done is emphasized. This highlights a common misconception in applying integration to variable forces in electrostatics.
Antonius
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Let's say Q is a charge at fixed position on the x - axis. There is another identical charge q on the y - axis. There is an electric force acting on q from Q (and it's not constant.) My question is can I find force acting upon q from Q to move q to a certain distance "a" , along y - axis (distance "a" from it's original position.)

Now that I have stated the conditions, my question - Can I integrate the Electric Force = q Q / ( 4 π ε ) ∫ 1 / r^2 to find the force that acts on q due Q which causes q to move a distance "a"

If you have a link to a source that explains this whole idea of varying electric force please let me know, that would be a massive help.

Thank you :)
 
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You already know the force. It's a variable force whsose magnitude at any point is given by coulombs law. If you integrate it with respect to dr, as you have suggested, you'll get work done by the force, not force.
 
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UncertaintyAjay said:
You already know the force. It's a variable force whsose magnitude at any point is given by coulombs law. If you integrate it with respect to dr, as you have suggested, you'll get work done by the force, not force.
Thanks a lot! Yesterday, I completely forgot that the area under F x d graph is a work done by the force...
 
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