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. cianfa72

    I Video: 'How electricity actually works'

    Hi, I found this interesting video about How electricity actually works. The point he makes (see for example the video at minute 7:23) is that the energy in a light bulb connected to a battery is actually transferred by the electromagnetic field and not by electrons flowing through it. The...
  2. E

    I Electric Potential in circuit

    I reviewed some of the fundamental physics and I looked back at the equation for Electric potential at a point p: $$V(p) = k \sum_{i} {\frac {q_i} {r_i}}$$ where - p is the point at which the potential is evaluated; - ri is the distance between point p and point i at which there is a nonzero...
  3. C

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  4. C

    Why Is the Electric Potential the Same for Inner and Outer Semi-Circles?

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  5. Z

    Two different dielectrics between parallel-plate capacitor

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  6. P

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  7. yucheng

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  8. Z

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  9. Jake357

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  10. Jake357

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  11. sinus

    I Grounded Means Zero Electric Potential: Exploring the Method of Images

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  12. C

    Calculating Electric Potential for a Non-Negligible Thickness Toroid

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  13. C

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  14. C

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  15. T

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  16. N

    Electric Potential Field Calculation

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  17. MatinSAR

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  18. J

    Velocity of two masses due to electric potential energy

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  19. G

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  20. A

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  21. L

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  22. iochoa2016

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  23. V

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  24. bluesteels

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  25. guyvsdcsniper

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  26. F

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  27. jaumzaum

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  28. yucheng

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  29. E

    I Co-rotating electric potential for KN solution

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  30. RodolfoM

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  31. J

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  32. A

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  33. Z

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  34. D

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  35. A

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  36. greg_rack

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  37. greg_rack

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  38. greg_rack

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  39. Athenian

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    My first attempt revolved mostly around the solution method shown in this "site" or PowerPoint: http://physics.gmu.edu/~joe/PHYS685/Topic4.pdf . However, after studying the content and writing down my answer for the monopole moment as equal to ##\sqrt{\frac{1}{4 \pi}} \rho##, I found out the...
  40. Sj4600

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  41. B

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    I used the potential at the surface of the sphere for my reference point for computing the potential at a point r < R in the sphere. The potential at the surface of the sphere is ## V(R) = k \frac {Q} {R} ##. To find the potential inside the sphere, I used the Electric field inside of an...
  42. D

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  43. Kaushik

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  44. F

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  45. hairey94

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  46. mcastillo356

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