I have one question regarding Kinetic Energy

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The discussion revolves around calculating the energy of a system with two charged particles, one with charge -q rotating around another with charge Q. The total energy is expressed as E = KE + U, where the potential energy U is given by U = -kQq/r1. The kinetic energy KE is stated as KE = kQq/2r1, and the participant seeks clarification on how this expression for kinetic energy is derived. The relationship between centripetal force and the attractive force between the charges is emphasized, linking it to the kinetic energy of the revolving charge. Ultimately, the participant expresses relief at understanding the concept after some confusion.
Tarabas
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The question is.
There are two particles, one with charge -q and the other with charge Q, and -q particle rotates around the Q particle at a radius r1. What is the Energy at this point?
The answer is like this: E= KE + U
So now I know that U= -kQq/r1
But according to the answer: KE= kQq/2r1. And I have no idea how they found this KE. Your help would be appreciated. Thanks in advance.
 
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If one charge is revolving around another, then there is a centripetal force acting on the revolving charge. Can you relate this to the attractive force between the charges? How does this relate to the kinetic energy of the revolving charge?
 
PWiz said:
If one charge is revolving around another, then there is a centripetal force acting on the revolving charge. Can you relate this to the attractive force between the charges? How does this relate to the kinetic energy of the revolving charge?
Thnx. I got it. Now I'm laughing how I couldn't figure it out .
 
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