What is Electric potential: Definition and 1000 Discussions

The electric potential (also called the electric field potential, potential drop, the electrostatic potential) is the amount of work energy needed to move a unit of electric charge from a reference point to the specific point in an electric field with negligible acceleration of the test charge to avoid producing kinetic energy or radiation by test charge. Typically, the reference point is the Earth or a point at infinity, although any point can be used. More precisely it is the energy per unit charge for a small test charge that does not disturb significantly the field and the charge distribution producing the field under consideration.
In classical electrostatics, the electrostatic field is a vector quantity which is expressed as the gradient of the electrostatic potential, which is a scalar quantity denoted by V or occasionally φ, equal to the electric potential energy of any charged particle at any location (measured in joules) divided by the charge of that particle (measured in coulombs). By dividing out the charge on the particle a quotient is obtained that is a property of the electric field itself. In short, electric potential is the electric potential energy per unit charge.
This value can be calculated in either a static (time-invariant) or a dynamic (varying with time) electric field at a specific time in units of joules per coulomb (J⋅C−1), or volts (V). The electric potential at infinity is assumed to be zero.
In electrodynamics, when time-varying fields are present, the electric field cannot be expressed only in terms of a scalar potential. Instead, the electric field can be expressed in terms of both the scalar electric potential and the magnetic vector potential. The electric potential and the magnetic vector potential together form a four vector, so that the two kinds of potential are mixed under Lorentz transformations.
Practically, electric potential is always a continuous function in space; Otherwise, the spatial derivative of it will yield a field with infinite magnitude, which is practically impossible. Even an idealized point charge has 1 ⁄ r potential, which is continuous everywhere except the origin. The electric field is not continuous across an idealized surface charge, but it is not infinite at any point. Therefore, the electric potential is continuous across an idealized surface charge. An idealized linear charge has ln(r) potential, which is continuous everywhere except on the linear charge.

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  1. fluidistic

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    Homework Statement Consider 2 conductor spherical shells of radii a and b (where a>b). The inner shell is at zero potential and the outer shell is at a potential given by ##V(\theta, \phi )=V_0 \sin \theta \cos \phi ## where ##V_0## is constant and theta and phi are the usual spherical...
  2. N

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  3. K

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  4. C

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  5. S

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  6. L

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  7. A

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  8. F

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  9. F

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  10. S

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  11. A

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  12. M

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  13. F

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  14. F

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  15. L

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  16. L

    Medical How Electrodes in salt solution can increase the electric potential

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  17. F

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    My question is: If you have a E= Ex+Ey+Ez To find V(x,y,z), i should: Just integrate Ex in order x? ∂V(x,y,z)/∂x = -Ex so: -V(x,y,z) = ∫Exdx or have i to sum the three integrals? -V(x,y,z) = ∫Exdx + ∫Eydy +∫Ezdz
  18. F

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  19. A

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  20. P

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  21. A

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  22. N

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  23. S

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  24. D

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  25. C

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  26. M

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  27. P

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  28. B

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  29. Jalo

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  30. N

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  31. N

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  32. H

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  34. K

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  35. A

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  36. A

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  37. N

    Electric Potential Inside Uniformly Charged Sphere

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  38. P

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  39. P

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  40. S

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  41. P

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  42. P

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  43. M

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  44. P

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  45. Z

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  46. Jalo

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  47. Jalo

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  48. Jalo

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  49. WannabeNewton

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  50. N

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