What is Electro static: Definition and 46 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. Silver2007

    Magnetic field due to electric wire

    In my opinion, the magnetic field at point P should cancel each other, because the magnetic field caused by the two wires has the same direction, like this. but the solution does not assume that the magnetic fields cancel each other out. I don't know where I'm wrong, please help me, thanks.
  2. M

    Engineering Current density calculation in anisotropic ferromagnetic film

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  3. J

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    I've figured out parts A and B but I'm struggling with Part C. I used the equation V = kQ1/r1 + kQ2/r2 where Q1 = -4.4e-12C ; k = 8.98755e9 r1 = 0.026 m Q2 = 27.4e-12 and r2 = .051-.026 My answer (8.329 V) is wrong but I have no idea why. Please help if you can.
  4. Harikesh_33

    I Question regarding Laplace's Equation for regions with charges

    Why doesn't the **Laplace's equation**(#\nabla^2V=0#) hold in the region within the sphere when there is a charge inside it ? Is it because #ρ \ne 0# within the sphere and it becomes a **poisson equation**($\nabla^2V=\dfrac{-ρ}{ε_0}$) and changes the characteristics of **Harmonic Solution**...
  5. C

    I Where to find this uniqueness theorem of electrostatics?

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  6. H

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  7. H

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  8. H

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  9. rudransh verma

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  10. rudransh verma

    B Why Are Electric Fields Perpendicular on a Charged Conductor's Surface?

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  11. bboo123

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  12. rudransh verma

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  13. jiajie

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  14. Narayanan KR

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  15. Z

    Boundary Value and Separation of Variables.

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  16. Z

    Question about the classic Image Problem

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  17. Data Base Erased

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    I know the energy is ##\frac{q²}{ 8 \pi \epsilon_{0}}( \frac{1}{a} - \frac{1}{b})##, but I can't get this result using the second equation. What I did: ##W = \frac{1}{2} \int \rho V d \tau ## ##\rho = \frac{q}{ \frac{4}{3} \pi r³}, a < r < b ## ##V = \frac{q}{4 \pi \epsilon_{0} r}## ## W =...
  18. O

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  19. Z

    Electric field direction on a grounded conducting sphere

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  20. torito_verdejo

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  21. navneet9431

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  22. Hawkingo

    Why there is a negative sign in the formula of calculating work done?

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  23. Mutatis

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  24. C

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  25. A

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  26. Manolisjam

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  27. L

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  28. Marcus95

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  29. Alettix

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  30. VSayantan

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  31. G

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  32. S

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  33. Turbotanten

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  34. Marcus95

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  35. NicolasPan

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  36. Narayanan KR

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    1. In above image an insulated metal plate has been placed inside Earth (soil), and an voltage is applied between plate and Earth groung what will be the capacitance here?? 2. one plate is the metal and the other plate is entire earth, so it is a big assymetrical Capacitor or What? all...
  37. V

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  38. A

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  39. annoyingdude666

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    hi, i still don't understand why infinite thin-walled cylindrical shell or conducting rod use lambda rather than sigma ? lambda = C/m ,,, sigma = C/m^2 i mean when we look at conducting rod, the charges inside the conductor is zero, so the charges spread on the surface of conducting rod(have...
  40. P

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  41. Gh778

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  42. marcophys

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  43. O

    Trying to compute electro static field

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  44. J

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  45. W

    Links Between Electromagnetic, Electro Static and Gravitational Fields?

    When Studying the properties of matter, I came across the properties of Gravity, electromagnetism and electro static fields I'm Wondering: As Gravity and Magnetic Fields a alike and some formulas for finding out the gravity are the same could the three have the same properties. (I have not...
  46. L

    How do electrostatic forces follow the principle of superposition?

    about electro static waves what is meant by the statement that "electro static waves follow the principle of super position"
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