
#1
Feb2812, 09:02 PM

P: 66

I dont really understand the concept of what makes work positive or negative for example if 3 charges are brought together from infinite what is the work done on them?
I am extremely confused about what make work positive and negative. 



#2
Feb2912, 05:20 AM

Sci Advisor
HW Helper
Thanks
P: 26,167

Hi Eats Dirt!
Potential energy = minus the work done by a conservative force. And work done = force "dot" displacement … so if the charge is attractive (like gravity), the force is in the same direction as displacement, so the work done by the force is positive, and the potential energy difference is negative 


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