Class 7 Science Chapter 3, Electricity: Circuits and their Components, starts with a school trip to the Bhakra Nangal hydroelectric powerhouse and builds a clear understanding of electric cells, batteries, incandescent and LED lamps, switches, circuit diagrams, conductors and insulators.
What Class 7 Science Chapter 3 Covers
3.1–3.2 A Torchlight & A Simple Electrical Circuit examines the positive and negative terminals of an electric cell (3.2.1), how cells combine in series to form a battery (3.2.2), filament lamps vs LEDs (3.2.3), and closed vs open circuits (3.2.4–3.2.5).
3.2.6–3.3 Electric Switch & Circuit Diagrams shows how a switch completes or breaks a circuit and introduces standard symbols for cells, batteries, bulbs, LEDs, switches and wires to draw clean circuit diagrams.
3.4 Electrical Conductors and Insulators tests metals, graphite, plastic, wood and rubber to classify electrical conductors and insulators and explain why wires have metal cores with plastic insulation.
Exercises in Chapter 3
- In a Nutshell key points summary and Let Us Enhance Our Learning chapter exercises.
- Exploratory Projects and Dive Deeper hands-on science activities.
Read Class 7 Science Chapter 3 Online
More Chapters
- Previous: Chapter 2: Exploring Substances: Acidic, Basic, and Neutral
- Next: Chapter 4: The World of Metals and Non-metals
- Hindi medium: Class 7 Science Chapter 3 PDF in Hindi (Jigyasa)
- All Science chapters and the other Class 7 books: Class 7 NCERT books 2026-27
- All Class 1 to 12 NCERT Textbooks: NCERT Books PDF (Class 1–12)
FAQ
Why does an LED have one longer lead and one shorter lead?
An LED glows only when its longer lead (positive terminal) is connected to the positive terminal of the battery and the shorter lead to the negative terminal.
What is the difference between an electric cell and a battery?
An electric cell is a single unit that converts chemical energy into electrical energy, whereas a battery is a combination of two or more cells connected together.