The Electric Potential Difference Created by Point Charges

AI Thread Summary
The discussion revolves around calculating the initial separation between two point charges after they are released from rest. The key equations involved include the electric potential difference, work-energy principle, and conservation of energy. Participants emphasize the importance of using kinetic energy and potential energy relationships, noting that the mass of the particles does not influence the potential difference. There is also mention of conservation of momentum, highlighting that the absence of external forces allows for momentum conservation in the system. The conversation underscores the need to find the speed of both particles to fully apply energy conservation principles.
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Homework Statement


One particle has a mass of 3.00 10-3 kg and a charge of +7.50 µC. A second particle has a mass of 6.00 10-3 kg and the same charge. The two particles are initially held in place and then released. The particles fly apart, and when the separation between them is 0.100 m, the speed of the 3.00 10-3 kg particle is 130 m/s. Find the initial separation between the particles.

Homework Equations


V = kQ/d
Vq=W
W=KE=1/2mv^2


The Attempt at a Solution



I don't really know where to start. I haven't seen any problems asking for initial separation before so I would appreciate it if someone could point me in the right direction.
 
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The basic principle is the conservation of energy. Start by finding the potential difference between the two states, one at separation d(say) and the other at separation 0.1m. This difference manifests as the kinetic energy of the particles. Can you proceed?
 
I understand that, but in order to calculate the kinetic energy of the particles, I need to know the speed of the other particle as well, because energy is conserved, which isn't given, so I'm not sure what to do after that. Also, if I'm not mistaken, mass doesn't affect the potential difference of a charge, right?
 
What about conservation of momentum, there is no external force so linear momentum is conserved.
 

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