Electrostatics and Coulomb's Law

Electrostatics

Coulomb's Law

• Coulomb's law describes the electrostatic force between two point charges.
• The magnitude of the electrostatic force is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance between them.
• Mathematically, $F<em>e \propto \frac{q</em>1 q_2}{r^2}$, where:
  • $F_e$ is the electrostatic force.
  • $q<em>1$ and $q</em>2$ are the magnitudes of the two point charges.
  • $r$ is the distance between the charges.
• The equation for Coulomb's law is: $F = K \frac{q<em>1 q</em>2}{r^2}$
  • $K$ is the Coulomb's constant, where $K = \frac{1}{4 \pi \epsilon_0}$
  • $\epsilon<em>0$ is the permittivity of free space, and $\epsilon</em>0 = 8.85 \times 10^{-12} C^2/N \cdot m^2$
  • $K = 9.0 \times 10^9 N \cdot m^2/C^2$