In this first lecture of Electrostatics, we begin with a brief overview of 2nd Year Physics, highlighting how this year focuses on deeper concepts such as waves, electricity, magnetism, and modern physics. These topics build a strong foundation for engineering, medical, and technological fields.

⚡ Introduction to Electrostatics

We then introduce the chapter Electrostatics, which deals with electric charges at rest and the forces between them.

🔹 Why Are We Studying Electrostatics?

Electrostatics helps us understand:

• How electric forces act between charged objects

• The working principles of electronic devices

• Lightning and atmospheric electricity

• Foundations of electric fields and electric potential

This chapter builds the base for understanding current electricity, capacitors, and electromagnetism.

🔋 What Are Static Charges?

Static charges are electric charges that remain at rest on the surface of an object.

Important points covered:

• Two types of charges: positive and negative

• Like charges repel, unlike charges attract

• Charging methods: friction, conduction, and induction

• Conservation of charge

📐 Coulomb’s Law

The lecture then explains Coulomb’s Law, which describes the force between two point charges.

It states:

The force between two point charges is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.

Mathematically:

F=kq1q2r2F = k \frac{q_1 q_2}{r^2}F=kr2q1​q2​​

where:

• $F$ = electrostatic force

• q1,q2q_1, q_2q1​,q2​ = magnitudes of charges

• $r$ = distance between charges

• $k$ = Coulomb’s constant

Key concepts discussed:

• Nature of force (attractive or repulsive)

• SI unit of charge (Coulomb)

• Unit of force (Newton)

• Inverse square law

By the end of this lecture, you will clearly understand static charges, the importance of electrostatics, and confidently apply Coulomb’s Law to solve conceptual and numerical problems.