I have one question regarding Kinetic Energy

AI Thread Summary
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
Messages
4
Reaction score
0
HW Template missing as it was moved from another forum
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.
 
Physics news on Phys.org
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 :)
 
  • Like
Likes bhobba and Tarabas
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Correct statement about a reservoir with an outlet pipe'
The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
Back
Top