Gravitational Pot. Engergy & Electrical Pot Energy

AI Thread Summary
Gravitational potential energy is defined as negative and calculated using the formula U = -GMm/R, while electrical potential energy can be either positive or negative, represented by V = kQq/R. The key distinction lies in the nature of mass and charge; mass is always positive and attracts, whereas electric charge can be positive or negative and may either attract or repel. To calculate changes in electrical potential energy (ΔEe), one can apply similar principles as with gravitational potential energy, considering the work done against an electric field. Understanding these differences is crucial for grasping the broader concepts of energy in physics.
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Homework Statement



Compare and contrast gravitational potential energy and electrical potential energy

Homework Equations



W=ΔEe (work=Δelectrical energy)

The Attempt at a Solution


I know what gravitational potential energy is but I don't quite understand what electrical potential energy is. I can grasp that electrical pot. energy is when you do work on a charged object against an electrical field. But how would you go about calculating ΔEe? Would it be similar to calculating gravitational potential energy where W=Force x Distance?

Thanks in advance.
 
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One interesting difference, we think of mass as some positive quantity, but electric charge comes in positive and negative quantities, (and color charge comes in 6 quantities). Masses attract, charges may or may not.
 
Last edited:
Spinnor said:
One interesting difference, we think of mass as some positive quantity, but electric charge comes in positive and negative quantities, (and color charge comes in 6 quantities). Masses attract, charges may or may not.

Not quite what was asked for but similar, gravitational potential energy is always negative,

U = -GMm/R

but electrostatic potential energy can be positive or negative,

V = kQq/R

Which gives rise to masses attract, charge may or may not.

(what of color potential energy, if there is such a thing, how might it go).
 
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