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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{\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.
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...
I have physics homework and came across this question :
I was asked to find the electrostatic force between two charged particles each having a charge of +5.0x10-9 C and which were separated by a distance of 3cm. I found it to be 2.5x10-4 N.Then I was told to calculate the gravitational force...
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|...
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...
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?
Homework Statement
A 8.15 nC charge is located 1.95 m from a 4.18 nC point charge.
(a) Find the magnitude of the electrostatic force that one charge exerts on the other.
N
(b) Is the force attractive or repulsive?
Homework Equations
The Attempt at a Solution
Is there really a...
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Homework Statement
Charge A is +2C and is located at <4,0,0>
Charge B is +12.5C and is located at <0,-3,0>
What is the the Force(AonB)
What is the magnitude of F(AonB)
Homework Equations
F = (k)(Qa)(Qb)/(r^2) (r^)
For reference the answers are
< -0.8k, 0.6k, 0 > N (F...
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!
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'...
Homework Statement
4 identical charges each equal to Q are placed at the 4 vertices of a regular triangular pyramid of each side equal to 'a'. Find the net electrostatic force on anyone charge.
Homework Equations
F = kQ^2/a^2
The Attempt at a Solution
find the force due to each...
Homework Statement
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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...
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.
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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...
Hi All
I'm a professional Electronics Engineer and very much an amateur physicist. I'm trying to find the force exerted between 2 parallel plates for a given plate voltage, separation, and plate area.
I've found plenty of wiki's, google pages etc etc of force between 2 point charges...
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-...
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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
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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...
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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...
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The figure is attached, please help, I'm so lost with physics II
Homework Statement
A charge of 6.00 x 10-9C and a charge of -3.00 x 10-9C are separated by a distance of 60.0 cm. Find the position at which a third charge, of 12.0 x 10-9C, can be placed so that the net electrostatic force on it is zero.
Homework Equations
Coulomb's Law
The...
Homework Statement
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 by about 0.28 nm. Calculate the electrostatic force between a sodium ion and a chloride...
Homework Statement
The problem is:
If you have 2 rectangular plates 1cmx10cm each, which means that the area is A=10cm2=10-3m2for each plate; every plate holds a Constant positive charge of Q=+2x10-6C each; these plates are separated by a distance d=1cm=10-2m
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Gravitation and electrostatic equations are standard.
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Homework Statement
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Homework Statement
Homework Equations
F = k*Q1*Q2/r^2
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Homework Statement
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Homework Statement
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Homework Statement
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Homework Statement
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Homework Statement
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(this is a direct cut and paste)
Homework Equations...
Homework Statement
Well we just learned about Coulomb's Law today but there is something that is bothering me. According to Coulomb's Law the magnitude of the force of attraction between a charged and neutral object is 0. However, the Law of Electrostatics states that a charged and neutral...
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Homework Equations
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I am trying to calculate the forces in a system with a mix of conductive + dielectric components upon application of an AC potential. Frequencies are low enough that I need not consider magnetic field effects. I can solve equations to obtain the electric field, but at am a loss for force...
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