1. Introduction to Electrostatics
- Electrostatics deals with the study of forces, fields, and potentials arising from static charges.
2. Coulomb's Law
- States that the force F between two point charges q1 and q2 is directly proportional to the
product of the magnitudes of the charges and inversely proportional to the square of the distance r
between them.
F = ke (q1 q2 / r^2)
- Here, ke is the electrostatic constant, ke = 1 / (4 pi epsilon_0), and epsilon_0 is the permittivity of
free space.
3. Electric Field (E)
- The electric field at a point is defined as the force per unit positive charge placed at that point.
E=F/q
- For a point charge q, the electric field at a distance r is:
E = ke (q / r^2) r_hat
- Superposition principle for electric fields: The net electric field due to multiple charges is the
vector sum of the electric fields due to individual charges.
4. Electric Field Lines
- Electric field lines are imaginary lines that represent the direction of the electric field at various
points in space.
- Properties:
- They originate from positive charges and terminate on negative charges.