Electrostatics and Coulomb's Law

Study Notes

Electrostatics

Electric Charges

Electric charges are of two types: positive and negative
Like charges repel each other, while opposite charges attract each other
The unit of electric charge is the coulomb (C)

Coulomb's Law

Describes the electrostatic force between two point charges
Force is proportional to the product of the charges and inversely proportional to the square of the distance between them
Mathematically represented as: F = k * (q1 * q2) / r^2
k is Coulomb's constant, approximately 8.99 x 10^9 N m^2 C^-2

Electric Field

A vector field that surrounds charged particles
Electric field lines emerge from positive charges and enter negative charges
The unit of electric field is newtons per coulomb (N/C)
Electric field can be calculated using Coulomb's Law

Electric Potential

Also known as voltage, it's the potential energy per unit charge
Measured in joules per coulomb (J/C) or volts (V)
Electric potential difference is the voltage between two points
Electric potential is a scalar quantity

Gauss's Law

Relates the distribution of electric charge to the resulting electric field
States that the total electric flux through a closed surface is proportional to the charge enclosed within the surface
Mathematically represented as: ∫E · dA = Q / ε₀
ε₀ is the electric constant (permittivity of free space)

Electric Dipole

A system of two equal and opposite charges separated by a small distance
Electric dipole moment is a measure of the strength of the dipole
Electric dipole moment is a vector quantity
Electric field due to an electric dipole decreases with distance

Electric Charges

Electric charges come in two types: positive and negative
Like charges repel each other, while opposite charges attract each other
The unit of electric charge is the coulomb (C)

Coulomb's Law

Describes the electrostatic force between two point charges
Force is proportional to the product of the charges and inversely proportional to the square of the distance between them
Mathematical representation: F = k * (q1 * q2) / r^2
k is Coulomb's constant, approximately 8.99 x 10^9 N m^2 C^-2

Electric Field

A vector field surrounding charged particles
Electric field lines emerge from positive charges and enter negative charges
Unit of electric field is newtons per coulomb (N/C)
Electric field can be calculated using Coulomb's Law

Electric Potential

Also known as voltage, it's the potential energy per unit charge
Measured in joules per coulomb (J/C) or volts (V)
Electric potential difference is the voltage between two points
Electric potential is a scalar quantity

Gauss's Law

Relates the distribution of electric charge to the resulting electric field
Total electric flux through a closed surface is proportional to the charge enclosed within the surface
Mathematical representation: ∫E · dA = Q / ε₀
ε₀ is the electric constant (permittivity of free space)

Electric Dipole

A system of two equal and opposite charges separated by a small distance
Electric dipole moment measures the strength of the dipole
Electric dipole moment is a vector quantity
Electric field due to an electric dipole decreases with distance

Description

Understand the basics of electric charges, Coulomb's Law and the electrostatic force between two point charges. Learn about the unit of electric charge and the mathematical representation of Coulomb's Law.