Two charges of +2x10 nc are 3 mm apart what is the force of repulsion between these two charges

In order to continue enjoying our site, we ask that you confirm your identity as a human. Thank you very much for your cooperation.

Better than just free, these books are also openly-licensed! The same content, but different versions (branded or not) have different licenses, as explained:

CC-BY-ND (branded versions)

You are allowed and encouraged to freely copy these versions. You can photocopy, print and distribute them as often as you like. You can download them onto your mobile phone, iPad, PC or flash drive. You can burn them to CD, email them around or upload them to your website. The only restriction is that you cannot adapt or change these versions of the textbooks, their content or covers in any way as they contain the relevant Siyavula brands, the sponsorship logos and are endorsed by the Department of Basic Education. For more information, visit Creative Commons Attribution-NoDerivs 3.0 Unported.

Find out more here about the sponsorships and partnerships with others that made the production of each of the open textbooks possible.

CC-BY (unbranded versions)

These unbranded versions of the same content are available for you to share, adapt, transform, modify or build upon in any way, with the only requirement being to give appropriate credit to Siyavula. For more information, visit Creative Commons Attribution 3.0 Unported.

This electric force calculator will enable you to determine the repulsive or attractive force between two static charged particles. Continue reading to get a better understanding of Coulomb's law, the conditions of its validity, and the physical interpretation of the obtained result.

Coulomb's law, otherwise known as Coulomb's inverse-square law, describes the electrostatic force acting between two charges. The force acts along the shortest line that joins the charges. It is repulsive if both charges have the same sign and attractive if they have opposite signs.

Coulomb's law is formulated as follows:

F = keq₁q₂/r²

where:

F is the electrostatic force between charges (in Newtons),
q₁ is the magnitude of the first charge (in Coulombs),
q₂ is the magnitude of the second charge (in Coulombs),
r is the shortest distance between the charges (in m),
ke is the Coulomb's constant. It is equal to 8.98755 × 10⁹ N·m²/C². This value is already embedded in the calculator - you don't have to remember it :)

Simply input any three values into our electric force calculator to obtain the fourth as a result.

To compute the electric potential at a point either due to a single point charge or a system of point charges, check out our electric potential calculator.

The unit of electric charge is a Coulomb (symbol: C). It is defined as the charge that is transported by a constant current of 1 ampere during 1 second. Hence, 1 C = 1 A * 1 s expressed in SI units.

If you don't remember what an ampere is, head to our Ohm's law calculator.

Three main conditions must be fulfilled for the electrostatic force calculator to return valid values:

Charges must be stationary - they cannot move with respect to each other.
Point charges are assumed. This assumption also holds for any charges that are spherical and symmetric. For example, a charged metal sphere fulfills this condition, but a charged metal box doesn't.
Charges cannot overlap - they must be distinct and have at least a minimal distance between them.

Force obtained with the help of our Coulomb's law calculator can be either positive or negative. Positive force implies a repulsive interaction between the charges. Negative force means that the interaction is attractive.

Did you notice that the default unit for charge in our Coulomb's law calculator is a nanoCoulomb (nC)? It is because the typical order of magnitude of an electric charge is 10-6 C or even 10-9 C.

Interested in electricity? Check out our electricity cost calculator, too!