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NCERT English Class 7 - Chapter 8: Fire: Friend and Foe - Notes

CBSEClass 7Englishआग: मित्र और शत्रु

Learning Objectives

  • Understand fire as both useful and dangerous
  • Learn about the fire triangle and how fire works
  • Know about fire safety and types of fires
  • Understand the history of fire discovery

Key Concepts

Discovery of Fire

Early humans discovered fire accidentally - possibly from lightning strikes or rubbing stones. Discovery of fire was a turning point in human civilization. It provided warmth, protection from wild animals, and ability to cook food.

Fire Triangle

Three things needed to make fire (Fire Triangle):

  1. Fuel: Material that burns (wood, paper, coal, gas)
  2. Oxygen: From air (supports burning)
  3. Heat: Enough heat to reach ignition temperature

Remove any one element and fire goes out. This is the principle behind fire-fighting.

Fire as a Friend

  • Cooking food
  • Keeping warm in cold weather
  • Generating electricity in thermal power plants
  • Running engines and vehicles
  • Industrial processes (smelting metals, making glass)
  • Lighting (historically, candles and oil lamps)

Fire as a Foe

  • Forest fires destroy vegetation and wildlife
  • House fires cause property damage and death
  • Industrial fires and explosions
  • Burns and injuries

Types of Fire and Extinguishing

  • Wood/paper fire: Use water (cools and cuts off oxygen)
  • Oil/petrol fire: NEVER use water (oil floats, fire spreads). Use foam, CO₂ extinguisher, or sand/soil.
  • Electrical fire: NEVER use water (risk of electrocution). Cut power supply first, then use CO₂ extinguisher.

Fire Safety

  • Install fire alarms and keep fire extinguishers handy
  • Know escape routes in buildings
  • If clothes catch fire: Stop, Drop, and Roll
  • Crawl low under smoke (smoke rises)
  • Never play with matches or lighters

Important Terms

  • Fire triangle: Fuel + Oxygen + Heat
  • Ignition temperature: Minimum temperature to start burning
  • Combustion: Process of burning
  • Extinguisher: Device to put out fire

Quick Revision

  • Fire Triangle: Fuel + Oxygen + Heat (remove one = no fire)
  • Friend: cooking, warmth, electricity, engines
  • Foe: forest fires, house fires, burns
  • Oil fire → NO water, use CO₂/sand
  • Electrical fire → cut power first, use CO₂
  • If clothes catch fire → Stop, Drop, Roll
NCERT English Class 7 - Chapter 8: Fire: Friend and Foe - Notes | EduMunch