What is the potential energy of this group of charges?

AI Thread Summary
The discussion revolves around calculating the potential energy of a system of three electrons arranged in an equilateral triangle with a proton at the center. The user attempted to apply the formula for potential energy but received feedback regarding incorrect dimensions in their answer. It was clarified that potential energy should be expressed in joules, not volts, which led to the user realizing their mistake. The conversation highlights the importance of understanding units in physics calculations. Ultimately, the user acknowledged the error and expressed gratitude for the clarification.
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Homework Statement


Three electrons form an equilateral triangle 0.800 nm on each side. A proton is at the center of the triangle.

Homework Equations


U = k[(q_1*q_2)/r]

The Attempt at a Solution


I tried to use the following equation:

k*[(3e^2)/(0.8*10^-9) - (3e^2)/(0.4*10^-9)]

I plugged in 1.602*10^-19 for both e-values, and got the following answer:

-6.4*10^-19 Volts

However, it says that "I do not have the correct dimensions." I'm not sure what that error means or what I did wrong, so any help would be appreciated.
 
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There's no question in your problem statement... thread titles don't really count as part of the problem statement. :smile:

"Dimensions" refer to the units associated with your answer. What are the units of potential energy, as opposed to electric potential?
 
gneill said:
There's no question in your problem statement... thread titles don't really count as part of the problem statement. :smile:

"Dimensions" refer to the units associated with your answer. What are the units of potential energy, as opposed to electric potential?

Oh my goodness what a dumb mistake! thank you!
 
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