What Does the Negative Sign in the Electrostatic Potential V Formula Represent?

AI Thread Summary
The negative sign in the electrostatic potential V formula indicates that work done in bringing a charge from infinity to a position is negative in attractive situations, such as between positive and negative charges. This reflects that energy is released as the charge moves closer, akin to a 'potential well' scenario. For a negative charge near a positive attractor, the potential energy is minimized when the charge is at rest in the well. To escape this influence, the charge must possess sufficient kinetic energy to overcome the negative potential energy. Understanding this concept is crucial for grasping electrostatic interactions.
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Potential at a position is defined as the Work Done in bringing a charge (or whatever) from infinity to that position. For an attractive situation (+ and - charges, for instance), the work 'put in' is negative, because you get work out. For a negative charge around an atom or a small mass near a large one, you can look upon it as being in a 'potential well', with the potential at a minimum if and when they 'land'. You can only leave the influence of the attractor if you have more kinetic energy (positive) than the negative potential energy due to position.
 
welcome to pf!

hi ap1993! welcome to pf! :wink:

yes, https://www.physicsforums.com/library.php?do=view_item&itemid=269" by a conservative force :smile:

eg, in gravity, PE increases when you go up, because the gravitational force is down

(and electric potential = potential energy per charge)
 
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thanks-i got it!
 

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