What is Electrostatics: Definition and 675 Discussions

Electrostatics is a branch of physics that studies electric charges at rest.
Since classical physics, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for amber, ήλεκτρον, or electron, was thus the source of the word 'electricity'. Electrostatic phenomena arise from the forces that electric charges exert on each other. Such forces are described by Coulomb's law.
Even though electrostatically induced forces seem to be rather weak, some electrostatic forces such as the one between an electron and a proton, that together make up a hydrogen atom, is about 36 orders of magnitude stronger than the gravitational force acting between them.
There are many examples of electrostatic phenomena, from those as simple as the attraction of the plastic wrap to one's hand after it is removed from a package to the apparently spontaneous explosion of grain silos, the damage of electronic components during manufacturing, and photocopier & laser printer operation. Electrostatics involves the buildup of charge on the surface of objects due to contact with other surfaces. Although charge exchange happens whenever any two surfaces contact and separate, the effects of charge exchange are usually only noticed when at least one of the surfaces has a high resistance to electrical flow. This is because the charges that transfer are trapped there for a time long enough for their effects to be observed. These charges then remain on the object until they either bleed off to ground or are quickly neutralized by a discharge: e.g., the familiar phenomenon of a static "shock" is caused by the neutralization of charge built up in the body from contact with insulated surfaces.

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  1. G

    Poisson's equation boundary conditions (electrostatics)

    Hi everyone! I have to solve a problem using Poisson's equation. There are two parallel infinite conductor planes in vacuum. The distance between them is d and they are both kept at a potential V=0. Between them there is a uniform volume density charge \rho_0>0 infinite along the directions...
  2. iVenky

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  3. CptXray

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  4. L

    At what point is Electric Potential zero

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  5. archaic

    Force of one distribution of charge on another

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  6. B

    No problem, happy to help! Keep up the good work in your studies.

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  7. N

    Electrostatics from particle laden air

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  8. A

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  9. yungquark

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  10. Abhimessi10

    Charge distribution on concentric spheres

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  11. Abhimessi10

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  12. Abhimessi10

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  13. ExplosivePete

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  14. Faizan Samad

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  15. N

    What is the issue with this electrostatics problem?

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  16. Captain Levi

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  17. O

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  18. O

    I Does a conductor E field include a tangential component?

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  19. Brilli

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  20. F

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  21. Brilli

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  22. G

    Calculate polarization energy over a set of cuboids

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  23. eigenmax

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  24. CDL

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  25. ubergewehr273

    Problem in electrostatics: E-field near 2 point charges

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  26. M

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  27. Hypercube

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  28. T

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  29. L

    Electrostatics on a metal sphere

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  30. S

    Apparent disagreement between Coulomb's Law and Gauss' Law

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  31. PKM

    What should be the electric field intensity inside a sphere

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  32. JustAStudent

    Work to move electron/proton between the plates of a charged capacitor?

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  33. Jayalk97

    Electrostatics: calculating the E-field of a line charge

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  34. A

    Electrostatics -- A charge oscillating through a charged plane

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  35. W

    Electrostatics: "Compressing" Charged Spherical Shell

    Homework Statement How much work is required to squeeze a uniformly charged spherical shell from a radius of ##r## to a radius of ##r−dr##, if (a) the total charge q is a constant, (b) the sphere is kept at a constant potential, e.g. grounded. (c) Are the answers the same or different...
  36. W

    Electrostatics: Energy from a charge distribution

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  37. Matt Chu

    Potential Energies of Two Charged Cylinders

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  38. L

    Calculate a charge distribution given an electric potential.

    Homework Statement Find the distribution of charge giving rise to an electric field whose potential is $$\Phi (x,y) = 2~tan^{-1}(\frac{1+x}{y}) + 2~tan^{-1}(\frac{1-x}{y})$$where x and y are Cartesian coordinates. Such a distribution is called a two-dimensional one since it does not depend on...
  39. Javier Lopez

    What would be the capacitance of a particle on a plate?

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  40. FritoTaco

    Electrostatics: graphing/field vectors

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  41. Jurtinus

    Coulomb's law, electrostatics?

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  42. Pushoam

    V(center) of charged metal sphere inside a grounded shell

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  43. Pushoam

    Flux through an infinite plane due to a point charge

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  44. Pushoam

    Elec. flux through the top side of a cube with q at a corner

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  45. Pushoam

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  46. Pushoam

    The energy lost in discharging a capacitor

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  47. S

    Electrostatics? Magnitude and direction of a magnetic field

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  48. Lazy Rat

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  49. VSayantan

    Electrostatics, Neutral Points

    Statement Four point charges, Q, -Q, Q, -Q, are placed at the four ends of a horizontal square of side a as shown in the figure above. What are the neutral points? The attempt at a solution The square is not exactly aligned parallel in its plane, say XY. So, the center is not a neutral point...
  50. V

    Find potential between 2 conc. cyl. with grounded strip

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