I have one question regarding Kinetic Energy

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Homework Help Overview

The discussion revolves around the kinetic energy of a particle with charge -q rotating around another particle with charge Q, focusing on the relationship between kinetic energy and potential energy in the context of electrostatics.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to understand how the kinetic energy expression KE = kQq/2r1 is derived, given the potential energy U = -kQq/r1. Some participants question the relationship between centripetal force and the attractive force between the charges, as well as its implications for kinetic energy.

Discussion Status

Participants are exploring the connections between forces and energy in the system. One participant expresses realization and understanding after considering the relationships discussed, indicating a productive direction in the conversation.

Contextual Notes

There may be assumptions regarding the nature of the forces acting on the charges and the conditions under which the kinetic energy is being evaluated. The original poster's confusion about the kinetic energy expression suggests a need for clarification on these assumptions.

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 .
 
Happens to the best of us :)
 
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