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,





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F

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k

e






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q

1



q

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r

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{\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. D

    Effect on electrostatic force due to dielectric medium.

    Hi! I have a high school physics question. I know the concept of induction, and I also know what happens when a dielectric slab is placed between 2 plates of a capacitor. 2 charged particles are kept at a distance r. The mutual force of attraction/repulsion is F. What happens to the force...
  2. M

    Electrostatic force and Gravitational force

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  3. D

    Electrostatic Force of a Triangle

    Homework Statement Suppose that the magnitude of the net electrostatic force exerted on the point charge q2 in the figure is 0.65 N . (Figure 1) http://imgur.com/4lZliPq Find the distance D. q1 = 2.1 micro C q2 = 6.3 micro C q3 = -.89 micro C Homework Equations F = k |q1|...
  4. Saxby

    Differentiating electrostatic force

    Homework Statement Obtain an expression for the potiential energy between to particles in an ionic bond at radius r0 Homework Equations Coloumb's laws: F = (-k * q1 * q2)/r-1The Attempt at a Solution I think that if i do U = r0∫0 F(r)dr = [k * q1 * q2 * r-1]r00 = k * q1 * q2 * r0-1, Then that's...
  5. S

    Electrostatic force on a parallel plate

    I'm tasked to find the force one parallel plate exert on the other plate in a capacitor. somehow the force isn't just F=qE, where E=Q/2εA What am I missing here?
  6. B

    How Do Charges Affect Electrostatic Force?

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  7. D

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  8. P

    Electrostatic force using vectors

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  9. S

    Magnitude of the electrostatic force

    Hello, Any help woould be wonderful! Identical point charges Q are placed at each of the four corners of a rectangle measuring 2.35 m by 3.05 m. If Q = 26.9 μC, what is the magnitude of the electrostatic force on anyone of the charges? i don't even know where to start... HELP!
  10. J

    Derive Electrostatic Force from Coulomb's Law.

    Homework Statement I should derive \vec{F_{q}} = \frac{-q'^{2}}{4∏ \epsilon_{0}} \frac{r'/a}{(r'^{2} - a^{2})} \hat{r} from \vec{F_{q''q'}} = k\frac{q' q''}{\left|\vec{x'} - \vec{x''}\right|^{2}} Homework Equations The Attempt at a Solution I know that q'' = -q'...
  11. B

    Net Electrostatic Force of 4 Charges at a Regular Triangle Pyramid

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  12. K

    Finding the angle for an electrostatic force

    Homework Statement What is the angle θ between the electrostatic force on the charge at the origin and the positive x-axis? Answer in degrees as an angle between -180 degrees and 180 degrees measured from the positive x-axis, with counterclockwise positive. Coulomb constant is 8.98755e9...
  13. W

    Magnitude and direction of the Electrostatic Force

    Homework Statement 3 identical charges of 2.0 uC are placed on the x-axis. The first charge is at the origin, the second to the right at x = 50cm, and the third is at the 100 cm mark. What are the magnitude and direction of the electrostatic force which acts on the charge at the origin...
  14. E

    Magnitude of total electrostatic force on a third particle ?

    Homework Statement A particle with charge −8 μC is located on the x-axis at the point 8 cm, and a second particle with charge −6 μC is placed on the x-axis at −6 cm. What is the magnitude of the total electrostatic force on a third particle with charge −4 μC placed on the x-axis at −2...
  15. M

    Find the order of magnitude of the electrostatic force

    Homework Statement Two engineering students, John with a mass of 90 kg and Mary with a mass of 45 kg, are 30 m apart. Suppose each has a 0.01% imbalance in the amount of positive and negative charge, with one student being positive and the other negative. Find the order of magnitude of the...
  16. H

    Calculating Electrostatic force between parallel plates

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  17. K

    Distance of Electrons with Electrostatic Force

    Homework Statement How far apart must two electrons be placed on the Earth's surface for there to be an electrostatic force between them equal to the weight of one of the electrons? Homework Equations Fe = (1 / 4∏ε0) X (q1q2 / r^2) The Attempt at a Solution I set Fe = me-...
  18. K

    Electrostatic force lab debate

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  19. S

    Calculating Electrostatic Repulsion in Nuclear Fission

    Homework Statement At the point of fission, a nucleus with 98 protons is divided into two smaller spheres, each with 49 protons and a radius of 6.38x10^-15 m. What is the repulsive force pushing these two spheres apart Hint: d ≠ the radius Homework Equations F= k (q1q2/d^2) The...
  20. F

    Are these two calculations of electrostatic force correct?

    I was watching a show the other night about the Large Hadron Collider, and I got to wondering how much force it would take to push two uranium nuclei right up against each other. I figured it would be on the order of a thousandth, maybe a millionth of a pound, which seems like a lot, considering...
  21. D

    Electrostatic force between point charge and dielectric ball.

    At a certain distance from a point charge q there is small, dielectric ball. How would change the value of electrostatic force acting on the ball, if the value of a point charge would be doubled? According to F=k[(q1*q1)/r^2] there would be no force on the dielectric ball, because his resultant...
  22. P

    Electrostatic Force between the sodium ion and the chloride ion.

    In solid sodium chloride (table salt), chloride ions have one more electron than they have protons, and sodium ions have one more proton than they have electrons. These ions are separated at about 0.28 nm. Calculate the electrostatic force between the sodium ion and the chloride ion. What I...
  23. B

    How Does Charge Polarity Affect Electrostatic Equilibrium Position?

    Homework Statement An electric point charge of Q1 = 5.23 nC is placed at the origin of the real axis. Another point charge of Q2 = 1.89 nC is placed at a position of p = 2.63 m on the real axis. At which position can a third point charge of q = -2.62 nC be placed so that the net...
  24. L

    Electrostatic force and magnitude problem

    In the figure, the net electrostatic force on Q1 is zero. If Q1 = +4.99 nC, determine the magnitude of Qo. Qo = (r0/r1)^2 * abs(q)*2cos theta The figure is attached, please help, I'm so lost with physics II
  25. C

    Electrostatic Force and Coulomb's Law

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  26. Y

    Electrostatic force between sodium ion and a chloride ion

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  27. O

    Electrostatic force between to spheres

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  28. P

    Electrostatic force between 2 distant parallel plates

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  29. P

    Electrostatic Force: Finding mA:mB Ratio

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  30. M

    Van der Waals and electrostatic force between polystyrene spheres

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  31. Q

    Electrostatic force between a charged ring and charged rod.

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  32. V

    Physics - Electrostatic Force Question

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  33. E

    Unraveling the Mystery of Electrostatic Force in Honeybees

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  34. J

    Net electrostatic force equals zero

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  35. C

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  36. S

    Coulomb's Law and electrostatic force

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  37. T

    Electrostatic Force Exerted Between Two Protons

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  38. C

    Electrostatic Force and Charge Transfer in a Collision between Polystyrene Balls

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  39. A

    Electrostatic Force in a Mad Scientist's Trap

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  40. X

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  41. D

    Electrostatic force between charged and neutral object?

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  42. A

    How Can I Increase Electrostatic Force in the Grinding Wheel Industry?

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  43. A

    Superposition and Electrostatic Force

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  44. T

    Balance of Forces - Electrostatic Force vs. Gravitational Force

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  45. P

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  46. R

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  47. M

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  48. A

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  49. C

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  50. M

    Direction of electrostatic force and field?

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