Probably a Dumb Question: How are E and (delta)V correlated?

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SUMMARY

The correlation between electric field (E) and electric potential (V) is defined by the equations ΔV = Ed and V = kq/r. When E = 0, the change in electric potential (ΔV) also equals 0, but this does not imply that V itself is 0; V can still have a value depending on the context. The first equation applies to uniform electric fields, while the second describes the potential from a point charge, indicating that the two equations are valid in different scenarios. The relationship between electric field and potential is expressed as E = -∇V, emphasizing that E is a vector quantity.

PREREQUISITES
  • Understanding of electric fields and potentials
  • Familiarity with the equations ΔV = Ed and V = kq/r
  • Basic knowledge of vector calculus
  • Concept of uniform versus non-uniform electric fields
NEXT STEPS
  • Study the concept of electric field lines and their relation to electric potential
  • Learn about the gradient operator in vector calculus and its application in electrostatics
  • Explore the implications of non-uniform electric fields on potential differences
  • Investigate the physical meaning of electric potential at infinity in electrostatics
USEFUL FOR

Students of physics, educators teaching electromagnetism, and anyone seeking to deepen their understanding of electric fields and potentials.

Iftekhar Uddin
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What I Think I Understand: ΔV = Ed (d being dstance) and that V = kq/r

please correct me if I'm misunderstanding those.

What I need to know: When E = 0, what happens to the electric potential? and vice versa.

Me Working it out: So if i use the first equation up here, If E = 0, then electric Potential = 0. Even with the second equation wouldn't I compare the net electric field with the net potential at a point? If so, then my answer remains the same. Either my equations are wrong or I'm really misunderstanding a simple concept. I may just be reaching my burnout point with physics right now. (I'm a few days in of focused physics studying and I can't wrap my head around simple concepts like this anymore.)
 
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Iftekhar Uddin said:
So if i use the first equation up here, If E = 0, then electric Potential = 0.
No; where E = 0 the change in electric potential = 0. (ΔV = 0)
 
Doc Al said:
No; where E = 0 the change in electric potential = 0. (ΔV = 0)

Then does that apply to just V as well? And thanks for the quick response! :)
 
Iftekhar Uddin said:
Then does that apply to just V as well?
If I understand you correctly, no.
 
Iftekhar Uddin said:
Even with the second equation wouldn't I compare the net electric field with the net potential at a point?
That second equation describes the potential at some distance from a positive charge. (It assumes V = 0 when infinitely far from the charge.)
 
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Iftekhar Uddin said:
What I Think I Understand: ΔV = Ed (d being dstance) and that V = kq/r

please correct me if I'm misunderstanding those.

What I need to know: When E = 0, what happens to the electric potential? and vice versa.

Me Working it out: So if i use the first equation up here, If E = 0, then electric Potential = 0. Even with the second equation wouldn't I compare the net electric field with the net potential at a point? If so, then my answer remains the same. Either my equations are wrong or I'm really misunderstanding a simple concept. I may just be reaching my burnout point with physics right now. (I'm a few days in of focused physics studying and I can't wrap my head around simple concepts like this anymore.)
The two equations that you gave are valid for two separate situations. ΔV = Ed is valid if the electric field is uniform. If it is not, then the relation is approximately valid only for short distances, and along a direction parallel to the field.
The second equation, V = kq/r gives the potential of a point charge q at the origin. In this case, the electric field is not uniform, so your first equation ΔV = Ed is not correct.
In all cases, the relation between electrostatic field and potential is: E = - ∇V. I typed E in bold to state that E is a vector.
 

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