CBSE Class 12 Physics: Chapter 1
Electric Charges and Fields - Comprehensive Study Notes
1. Electric Charge
Electric charge is a fundamental physical property of matter that causes it to
experience a force when placed in an electromagnetic field. There are two types of
charges: Positive and Negative.
Basic Properties of Electric Charge:
• Additivity of Charges: Total charge of a system is the algebraic sum of
individual charges.
• Conservation of Charge: Total charge of an isolated system remains
constant.
• Quantization of Charge: Charge exists in discrete packets. The charge q on
a body is given by:
q = ±ne
Where n is an integer and e is the elementary charge (≈ 1.6 × 10⁻¹⁹ C).
2. Coulomb's Law
The magnitude of the electrostatic force of attraction or repulsion between two point
charges is directly proportional to the product of the magnitudes of charges and
inversely proportional to the square of the distance between them.
F = k * (|q₁q₂| / r²)
Page 1
Electric Charges and Fields - Comprehensive Study Notes
1. Electric Charge
Electric charge is a fundamental physical property of matter that causes it to
experience a force when placed in an electromagnetic field. There are two types of
charges: Positive and Negative.
Basic Properties of Electric Charge:
• Additivity of Charges: Total charge of a system is the algebraic sum of
individual charges.
• Conservation of Charge: Total charge of an isolated system remains
constant.
• Quantization of Charge: Charge exists in discrete packets. The charge q on
a body is given by:
q = ±ne
Where n is an integer and e is the elementary charge (≈ 1.6 × 10⁻¹⁹ C).
2. Coulomb's Law
The magnitude of the electrostatic force of attraction or repulsion between two point
charges is directly proportional to the product of the magnitudes of charges and
inversely proportional to the square of the distance between them.
F = k * (|q₁q₂| / r²)
Page 1
