# Electrical force between charges

• Latsabb
In summary, the problem was to find the magnitude of the electrostatic force on a point 3 meters from q1, which has a charge of 3μC. The formula used was Feq1=1/(4πε0)*(q1/r), but was incorrect as it did not include r2 in the denominator. Once this was corrected, the correct calculation for the force was found to be 89.9kN, which may seem large but is in fact the correct value.
Latsabb
edit: I see that my title is incorrect. This isn't between charges, it is between a charge and a point, sorry about that.

The problem:
Find the magnitude of the electrostatic force that works on a point 3 meters from q1.

q1=3μC

My attempts:
Feq1=1/(4πε0)*(q1/r)
r=3m
1/(4πε0)=8.988x109

Feq1=8.988x109*(3x10-6/3)=89.9kN

As far as I can tell, this is the way it should be done, but the force seems pretty large... Is there something that I am missing? Or is this actually correct?

Latsabb said:
edit: I see that my title is incorrect. This isn't between charges, it is between a charge and a point, sorry about that.

The problem:
Find the magnitude of the electrostatic force that works on a point 3 meters from q1.

q1=3μC

My attempts:
Feq1=1/(4πε0)*(q1/r)
r=3m
1/(4πε0)=8.988x109

Feq1=8.988x109*(3x10-6/3)=89.9kN

As far as I can tell, this is the way it should be done, but the force seems pretty large... Is there something that I am missing? Or is this actually correct?

Well, you can start by checking the units in your calculation, in particular Coulomb's constant. Are your formula and calculation dimensionally correct?

Coulombs constant is N·m²/C², while q1/r would be C/m. So put together that would give me N*m/c... That means that there should be a C²/m², which I know to be q0*q1/r2 but that is between two charges, not the force at a point.

I guess that means that Feq1=1/(4πε0)*(q1/r) isn't an actual equation? Which leaves me confused, because that is what was given to me in someone's notes...

I spoke with the person I got the notes from, and it should have been r2 in the denominator, which would give me N/C, or the field strength. Thank you for your help.

I can confirm that your calculation is correct. The electrostatic force between two point charges is given by Coulomb's Law, which states that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. In this case, the distance is 3 meters and the charge is 3 microCoulombs, which results in a relatively large force of 89.9 kiloNewtons. This may seem like a large force, but it is important to remember that the electrostatic force is one of the fundamental forces of nature and can be quite strong, especially when dealing with large charges. Additionally, the force may seem large in comparison to everyday objects, but on an atomic or molecular scale, it may be relatively small. Overall, your calculation is correct and there is no need to be concerned about the magnitude of the force.

## What is electrical force between charges?

The electrical force between charges is the force that exists between two charged particles. It is a fundamental force of nature that is responsible for the interactions between charged particles, such as electrons and protons.

## How is electrical force between charges calculated?

The electrical force between charges is calculated using Coulomb's law, which states that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.

## What factors affect the strength of electrical force between charges?

The strength of electrical force between charges is affected by the magnitude of the charges involved and the distance between them. The force increases as the charges get larger and decreases as the distance between them increases.

## What is the difference between electrical force and gravitational force?

Electrical force and gravitational force are both fundamental forces of nature, but they have some key differences. Electrical force is caused by the interactions between charged particles, while gravitational force is caused by the mass of objects. Electrical force can be attractive or repulsive, while gravitational force is always attractive.

## How is electrical force between charges used in everyday life?

Electrical force between charges is used in a wide range of everyday applications, such as in electronic devices, power lines, and electric motors. It is also the basis for many important technologies, including electricity generation and transmission, telecommunications, and medical imaging.

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