Fire: Friend and Foe
Overview
Fire: Friend and Foe is an informational prose chapter from NCERT Class 7 English (Honeycomb) that explains the science of fire, its uses and dangers. The chapter describes how fire is produced, what conditions are needed to start and sustain it, how it can be controlled, and how firefighters tackle blazes. It balances the positive and negative aspects of fire, helping students understand why fire is called both a friend and a foe.
Typed Notes
What is Fire and How Does It Start?
Fire is a chemical reaction that produces heat and light. For fire to start and keep burning, three things must be present at the same time: fuel (something that can burn, like wood or paper), heat (enough temperature to ignite the fuel), and oxygen (from the air). These three elements together form what scientists call the 'fire triangle.' If any one of these three is missing or removed, the fire cannot start or will go out. This is the basic science behind both starting and stopping a fire.
Fire as a Friend — Its Uses
Fire has been one of the most important discoveries in human history. It keeps us warm in cold weather and is used for cooking food. Industries use fire to make metals, glass, and many other products. Fire is also used in engines that power vehicles and machines. In earlier times, fire was used to scare away wild animals and to give light in the dark. Even today, fire plays a vital role in everyday life, making it one of humanity's most valuable tools and a true friend when used carefully.
Fire as a Foe — Its Dangers and How to Fight It
When fire goes out of control, it becomes extremely dangerous. It can destroy homes, forests, and factories, and can kill people and animals. Different types of fires need different methods to put them out. Water is used for wood or paper fires because it cools the fuel and removes oxygen. However, water should never be used on oil fires or electrical fires as it can spread the flames or cause electric shocks. Sand, foam, or carbon dioxide extinguishers are used instead. Firefighters are specially trained to handle these dangerous situations safely and effectively.
Controlling Fire — The Science of Extinguishing
Since fire needs fuel, heat, and oxygen to survive, we can stop it by removing any one of these. Pouring water removes heat and blocks oxygen. Covering a small fire with a lid or blanket removes oxygen. Clearing dry leaves and trees in the path of a forest fire removes fuel. Fire extinguishers spray chemicals that cut off oxygen or cool the fire. Understanding the fire triangle helps us choose the right method to fight each type of fire. This scientific knowledge makes fire-fighting more effective and prevents unnecessary damage.
Key Concepts
Revision ke liye ek nazar — exam se pehle yahi padhna hai.
- 01Fire needs three things to burn: fuel, heat, and oxygen — together called the 'fire triangle'.
- 02Removing any one side of the fire triangle puts out the fire.
- 03Water cools burning material and cuts off oxygen, which is why it is used to fight fires.
- 04Different fires (wood, oil, electrical) need different methods to extinguish them.
- 05Fire has been essential to human civilization for cooking, warmth, and industry, but it can also destroy life and property.
Questions & Solutions
Pehle khud try karo — phir solution kholo. Yahi tariqa topper banata hai.
What is the 'fire triangle' and why is it important?
Why should water not be used to put out an oil fire or an electrical fire?
In what ways is fire a good friend to human beings?
How do firefighters use the idea of the fire triangle to put out fires?
What method would you use to put out a small fire in a frying pan, and why?
Fire: Friend and Foe explains the science of fire using the concept of the fire triangle — fuel, heat, and oxygen. Fire is a friend because it helps in cooking, warmth, and industry. It becomes a foe when it goes out of control and destroys life and property. Different fires are fought using different methods. Removing any one element of the fire triangle extinguishes the fire.
Chapter-end quiz
4 MCQsOption tap karo — turant pata chalega sahi ya galat, explanation ke saath.
Q1.Which of the following is NOT part of the fire triangle?
Q2.Why is carbon dioxide used in fire extinguishers?
Q3.What does the word 'ignite' mean?
Q4.Which sentence uses the word 'extinguish' correctly?
Mark karo — dashboard par progress dikhega.