Class 12 Physics Chapter 1: Electric Charges and Fields
Chapter 1 of the NCERT Class 12 Physics textbook “Physics Part I”.
Chapter at a glance
This part introduces electric charge as a basic property of matter, how two point charges exert force on each other (Coulomb's law), and the idea of electric field as the space influence produced by a charge. We study charge conservation, quantisation, conductors and insulators briefly. Then we learn Coulomb's law, superposition principle and define electric field with the field of a single point charge.
What you will learn: You will learn what electric charge is, Coulomb's law for force between point charges, the superposition principle, and the definition and formula for electric field due to a point charge.
Why it matters: These are the fundamentals for all electrostatics problems: forces between charges, how many charges combine, and how charges create fields that act on other charges even without contact.
Key concepts
- Electric charge (basic properties) — Electric charge is a measurable property that causes electrostatic forces.
- Coulomb's law and superposition — Coulomb's law gives the magnitude and direction of force between two point charges.
- Electric field (definition and field of a point charge) — Electric field at a point is the force per unit positive test charge placed there.
What the chapter covers
- Try at Home — A safe observation to feel electrostatic attraction with common items.
- Why Questions — Short reasoning questions to deepen intuition.
Remember for the exam
- Always use SI units: C, m, N, F/m.
- State direction clearly for vector answers.
Common mistakes
- Mistake: Adding forces as scalars without direction. Better: Resolve each force into components and add vectorially.
- Mistake: Forgetting to indicate direction of vector answer. Better: State direction in words and, if possible, give unit vector or angle.
- Mistake: Treating extended charged bodies as point charges without justification. Better: Use point-charge formula only when allowed by problem; otherwise prepare to integrate (later parts) or use symmetry/Gauss's law.
These notes are a study aid. Check important facts against your textbook.
Study this chapter
- A clear study guide that explains the chapter step by step
- Quick revision for the day before a test
- Practice quizzes that show which ideas need more work
- An AI tutor to ask questions about “Electric Charges and Fields”
More in Class 12 Physics
Chapter names follow the current NCERT textbooks. My Study Mantra does not reproduce textbook pages.