Power needs control Do you agree or not, give your response in the
reference to the chapter "fire
Friend and Foe?
Answers
Answer:
Question 1.
What is early man’s outlook for fire?
Answer:
He was scared of fire. The early man might have seen volcanoes or lighting before he started using fire and was hence knew it was dangerous and powerful.
Question 2.
Give some examples of fuel.
Answer:
Wood, coal, cooking gas and petrol are examples of fuel.
Question 3.
Why gaps are left between buildings during construction?
Answer:
Gaps are left between buildings during construction to reduce the risk of fire.
Question 4.
How has the discovery of fire helped the mankind?
Answer:
Discovery of fire has helped the early man to cope with nature. It also helped them adopt a settle mode of life.
Question 5.
How fire is a good servant?
Answer:
Fire is a good servant. When kept under control fire helps us do many things in most of our home we cook our food on fire. We use fire to keep us warm during extreme winter. It is also used to generating electricity.
Question 6.
Before fire brigades were set out, how people tried to put out fire.
Answer:
Before the fire brigade came into the picture people used to extinguish fire forming human chain. Everyone was a fireman in that scenario. People used to pass buckets filled with water from a pond or well through each other and the person at the extreme end used to pour it over the flames.
Question 7.
How have we learnt to control fire?
Answer:
Every year we spend millions of rupees for fighting fires. We spend even large sum of money to find out ways to prevent fire from happening and going out control in the process we have learnt to control fire and use it for our betterment.
Question 8.
Explain with an example how can you put out fire by cutting the supply of oxygen.
Answer:
Oxygen is one of the three elements essential for causing fire. If we can disrupt the supply of oxygen then we can put of the fire. This can be applied in case of small fires. If we throw a damp blanket or a sack over fire. It cuts off the supply of oxygen and the fire is immediately put off.
Question 9.
Why we cannot use water to put out some fires?
Answer:
We cannot use water in case of oil and electric fires oil floats over water and thus oil fires cannot be extinguished using water. Water flows on and it has the risk of spreading the fire along. In case of electric fires water cannot be used as an extinguished. It being a good conductor of electricity puts the life of the man spraying it in danger.
Question 10.
What is the role of fire fighter?
Answer:
Fire fighters are given training on various skills to minimize the damage. They put out fire and also give first aid.
Question 11.
What do you understand by the ‘flash point’ of a fuel?
Answer:
The temperature at which a fuel begins to burns is called its flash point.
Question 12.
(i) What are some common uses of fire?
(ii) In what sense is it a “bad master”?
Answer:
(i) The common uses of fire are to cook food, warm our names in winter, to generate electricity and many more.
(ii) If fire goes out of control, it can cause damage to our life, house and property. It is ‘bad master’ in this sense.
Explanation: