Class 12 Physics - Chapter 1: Electric Charges and Fields Revision Notes

Vocabulary flashcards focusing on definitions, units, and fundamental laws of Electric Charges and Fields.

Electric Charge

A fundamental property of matter that can be positive or negative, with the SI unit Coulomb ($C$); like charges repel and unlike charges attract.

Quantization

A property of electric charge described by the formula $Q = ne$, where charge exists in discrete packets.

Coulomb's Law

States that the force ($F$) between two point charges is directly proportional to the product of charges and inversely proportional to the square of the distance: $F = \frac{k q_1 q_2}{r^2}$.

Electric Field

The region around a charge where another charge experiences a force, defined as $E = \frac{F}{q}$ with the unit $N/C$.

Electric Field Lines

Visual representations of the electric field that start from positive charges, end at negative charges, and never intersect; closer lines indicate a stronger field.

Electric Dipole

A system consisting of two equal and opposite charges separated by a small distance.

Dipole Moment

Represented by the formula $p = q \times 2a$, describing the strength and orientation of an electric dipole.

Electric Flux

A measure of the electric field passing through a surface, calculated as $\text{Φ} = EA \text{cos}(\theta)$ with the unit $N \text{ } m^2/C$.

Gauss's Theorem

States that the total electric flux through a closed surface equals the enclosed charge ($Q$) divided by $\text{ε}_0$ ($\text{Φ} = \frac{Q}{\text{ε}_0}$).

Conservation of Charge

One of the fundamental properties of charge, stating that total charge in an isolated system remains constant.

Additivity of Charge

The property stating that the total charge of a system is the algebraic sum of all individual charges.