Coulomb’s law

Definition

Coulomb's Law quantifies the electrostatic force between two charged objects. The force is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.

5 Must Know Facts For Your Next Test

1. Coulomb's Law formula is $F = k \frac{q_1 q_2}{r^2}$, where $F$ is the electrostatic force, $k$ is Coulomb's constant ($8.99 \times 10^9 \text{Nm}^2/\text{C}^2$), $q_1$ and $q_2$ are the charges, and $r$ is the distance between them.
2. The direction of the force depends on the signs of the charges: like charges repel and opposite charges attract.
3. Coulomb's Law applies to point charges or spherically symmetric charge distributions.
4. The law assumes that other forces (e.g., gravitational) are negligible compared to electrostatic forces in most practical scenarios.
5. In a vacuum, Coulomb's constant ($k$) has a value determined by the permittivity of free space ($\epsilon_0$), where $k = \frac{1}{4\pi\epsilon_0}$.

Review Questions

Related terms

Electric Charge:

A fundamental property of matter that causes it to experience a force when placed in an electromagnetic field. It can be positive or negative.

Electric Field:

A field around charged particles that exerts a force on other charged particles. Its strength is measured in volts per meter (V/m).

Permittivity:

$\epsilon_0$, also known as permittivity of free space, is a constant representing how much resistance is encountered when forming an electric field in a vacuum.