F = k * (q1 * q2) / r²

Where:

* F is the electric force in Newtons (N)

* k is Coulomb's constant, approximately 8.98755 × 10⁹ N⋅m²/C²

* q1 and q2 are the magnitudes of the two charges in Coulombs (C)

* r is the distance between the centers of the two charges in meters (m)

Important Considerations:

* Direction: The force is attractive if the charges have opposite signs (one positive and one negative) and repulsive if they have the same sign (both positive or both negative).

* Vector Nature: The force is a vector quantity, meaning it has both magnitude and direction.

* Units: Make sure to use consistent units for all quantities.

Example:

Let's say we have two charges:

* q1 = +2.0 x 10⁻⁶ C

* q2 = -1.0 x 10⁻⁶ C

* r = 0.05 m

We can calculate the electric force between them as follows:

1. Plug in the values:

F = (8.98755 × 10⁹ N⋅m²/C²) * (2.0 x 10⁻⁶ C) * (-1.0 x 10⁻⁶ C) / (0.05 m)²

2. Calculate:

F = -0.719 N

3. Interpret: The force is negative, indicating that the charges are attracted to each other. The magnitude of the force is 0.719 N.

Note: The negative sign in the example indicates that the force is attractive.