Chapter 1: Electric Charges and Fields
Electric charge is a fundamental property of matter that gives rise to electric forces and fields.
1. **Electric Charge**:
- Charges are of two types: Positive (+) and Negative (-).
- Like charges repel, and unlike charges attract.
- SI unit: Coulomb (C).
2. **Coulomb's Law**:
- The force (F) between two charges q1 and q2 separated by distance r is given by:
F = k * (q1 * q2) / r²
- Where k = 9 × 10^9 Nm²/C² (Coulomb's constant).
3. **Electric Field (E)**:
- Electric field at a point due to a charge q is given by:
E = F / q = k * q / r²
- Direction: Away from positive charge, toward negative charge.
4. **Electric Field Lines**:
- Imaginary lines representing the direction of the electric field.
- Lines never cross.
- Denser lines indicate a stronger field.
5. **Electric Flux (Phi)**:
- Measures the number of electric field lines passing through a surface.
- Phi = E * A * cos(theta), where A is the surface area and theta is the angle between E and A.
Electric charge is a fundamental property of matter that gives rise to electric forces and fields.
1. **Electric Charge**:
- Charges are of two types: Positive (+) and Negative (-).
- Like charges repel, and unlike charges attract.
- SI unit: Coulomb (C).
2. **Coulomb's Law**:
- The force (F) between two charges q1 and q2 separated by distance r is given by:
F = k * (q1 * q2) / r²
- Where k = 9 × 10^9 Nm²/C² (Coulomb's constant).
3. **Electric Field (E)**:
- Electric field at a point due to a charge q is given by:
E = F / q = k * q / r²
- Direction: Away from positive charge, toward negative charge.
4. **Electric Field Lines**:
- Imaginary lines representing the direction of the electric field.
- Lines never cross.
- Denser lines indicate a stronger field.
5. **Electric Flux (Phi)**:
- Measures the number of electric field lines passing through a surface.
- Phi = E * A * cos(theta), where A is the surface area and theta is the angle between E and A.
