Electric Potential and Kinetic Energy

AI Thread Summary
The discussion focuses on a physics problem involving two identical point charges and their kinetic energy when released from rest. The user attempts to apply the principle of conservation of energy, specifically the relationship between kinetic energy (KE) and potential energy (PE). There is confusion regarding the calculation, as the user initially considers only one charge instead of both. It is emphasized that the total change in kinetic energy for both charges must be accounted for in the solution. The conversation highlights the importance of correctly applying conservation laws in multi-body systems.
jakey
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Homework Statement



Two identical +9.5e-6C point charges are initially 3.5 cm from each other. If they are released at the same instant from rest, how fast will each be moving when they are very far from each other? Assume they have identical masses of 1.0mg.

Homework Equations



im not sure with this though but i used D(KE) + D(PE) = 0 where D=delta


The Attempt at a Solution


i used the above equation to solve for v. i kinda considered the problem by taking 1 point charge. however, i can't get the right answer...
 
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jakey said:
i kinda considered the problem by taking 1 point charge.
What do you mean by that?

There are two point charges. Make sure you consider the total change in KE of both of them.
 

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