What is Electrostatic force: Definition and 184 Discussions

Coulomb's law, or Coulomb's inverse-square law, is an experimental law of physics that quantifies the amount of force between two stationary, electrically charged particles. The electric force between charged bodies at rest is conventionally called electrostatic force or Coulomb force. The law was first discovered in 1785 by French physicist Charles-Augustin de Coulomb, hence the name. Coulomb's law was essential to the development of the theory of electromagnetism, maybe even its starting point, as it made it possible to discuss the quantity of electric charge in a meaningful way.The law states that the magnitude of the electrostatic force of attraction or repulsion between two point charges is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them,





|

F

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=

k

e






|


q

1



q

2



|



r

2






{\displaystyle |F|=k_{\text{e}}{\frac {|q_{1}q_{2}|}{r^{2}}}}
Here, ke is Coulomb's constant (ke ≈ 8.988×109 N⋅m2⋅C−2), q1 and q2 are the signed magnitudes of the charges, and the scalar r is the distance between the charges.
The force is along the straight line joining the two charges. If the charges have the same sign, the electrostatic force between them is repulsive; if they have different signs, the force between them is attractive.
Being an inverse-square law, the law is analogous to Isaac Newton's inverse-square law of universal gravitation, but gravitational forces are always attractive, while electrostatic forces can be attractive or repulsive. Coulomb's law can be used to derive Gauss's law, and vice versa. In the case of a single stationary point charge, the two laws are equivalent, expressing the same physical law in different ways. The law has been tested extensively, and observations have upheld the law on the scale from 10−16 m to 108 m.

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  1. B

    How Do You Calculate Electrostatic Force Between Charges?

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  2. Ranku

    Meaning of formula of electrostatic force

    The formula for Coulomb's force is F = k \frac{q_{1}q_{2}}{r^{2}}, which represents how the force varies as the inverse square of distance between like or unlike charges. Does it mean the repulsive force between like charges decreases as the inverse square of distance?
  3. K

    What is the work done by the electrostatic force

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  4. S

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  5. K

    Electrostatic force betwen two ions

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  6. B

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  7. H

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  8. S

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  9. C

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  10. O

    Calculating Net Charge on a Metal Sphere with Added Electrons

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  11. A

    Electrostatic force on a charge

    i was reading the book of Griffin - introduction to electrodynamics. it is written that the force of charge q on Q is not only depends on the distance b.w them but also the velocity & acceleration of charge q.then i think coloumb'law is incomplete at all. it must include some quantity for...
  12. A

    Calculating Electrostatic Force with Coulomb's Law

    Four point-charges are fixed at the corners of a 3.0m X 4.0m rectangle. The coordinates of the corners and the values of the charges are listed below. q1 = 100 microC (0, 4m), q2 = 36 microC (4m, 3m), q3 = 125 microC (0, 3m) and q4 = 32 microC (0,0). Compute the net electrostatic force acting on...
  13. P

    Electrostatic Force: -0.7nC Charge at Origin

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  14. S

    Find net electrostatic force

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  15. M

    Electrostatic force of attraction between two particles

    The homework problem reads as follows: A proton and an electron are held in place on the x axis. The proton is at x=-d, while the electron is at x=+d. They are released simultaneously, and the only force that affects their motions is the electrostatic force of attraction that each applies...
  16. J

    Electrostatic Force: Learn About Its Effects

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  17. N

    Coulomb's Law, net electrostatic force

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  18. A

    Electrostatic Force Equation Help

    I'm doing a video analysis and there is a charged ball that a woman is holding and there is another charged ball hanging from a string with length L. The video is of the woman pushing the ball closer to the ball from the string and how it pushes it away and I am using LoggerPro to analyze the...
  19. K

    How Do You Calculate the Net Electrostatic Force on a Central Charge?

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  20. N

    AnswerSolving Electrostatic Force: Find Charge & Mass

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  21. Z

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    Homework Statement Measurements show that a honeybee in active flight can acquire an electrostatic charge on the order of 93 pC. a)How many electrons much be transferred to produce this charge? Ne = * b) Supposing two bees, both with this charge, are separated by a distance of 12 cm...
  22. S

    Magnitude of the Net Electrostatic Force On an Oxygen Atom

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  23. H

    Net Electrostatic Force on a neg charge next to a pos charge inbetween a field

    Homework Statement Two point charges, Q1 = -6.9 µC and Q2 = 1.1 µC are located between two oppositely charged parallel plates, as shown in Fig. 16-65. The two charges are separated by a distance of x = 0.38 m. Assume that the electric field produced by the charged plates is uniform and equal...
  24. A

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  25. F

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  26. A

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  27. J

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  28. M

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  29. J

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  30. J

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  31. S

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  32. T

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  33. H

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  34. L

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  35. C

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  36. B

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  37. C

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  38. A

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  39. A

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  40. U

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  41. G

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  42. J

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  43. M

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  44. M

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  45. M

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  46. Y

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  47. A

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  48. H

    Find electrostatic force between

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  49. P

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  50. I

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