An Overview of Ncert Solutions Class 12 Micro Economics
1. Fill in the Blanks:
________ used to blow on his hands to keep them warm in the winter.
The instrument used to hear the heartbeats is called ___________.
________ thought woodcutter was a dangerous creature.
In a minute an adult breathes about _____ to _____ times.
The woodcutter picked up the two stones and made a _________.
2. Choose the correct option out of the following:
Which of the following instruments is used by doctors to listen to the heartbeats of a patient?
Stethoscope
Telescope
Stethoscope
Microscope
Gyroscope
Infants can have up to ______ breathes per minute.
28
41
34
44
Which of the following is an air-played musical instrument?
Flute
Guitar
Tabla
Drums
Our heart beats faster when we do which of the following?
Sleeping
Sitting
Running
Meditating
3. Name the musical instruments shown in the Picture.
4. What is the easiest way of warming hands in winter?
5. How does it feel when we warm our cold hands?
6. Why does hot air rise up and cold air comes down?
7. Match the following from column 1 to column 2:
8. Who is a woodcutter?
9. Why does the mirror gather water droplets when we blow on it?
10. Who was the curious little man in the story?
11. Why do we blow on hot objects?
12. What would happen if we ate hot objects?
13. What does a woodcutter do in winter?
14. Why does the woodcutter cope with the cold?
15. Who wrote the story Blow hot,Blow cold?
16. Put your hand in front of your mouth and blow air. What do you observe?
17. Put your hand a little bit away from your mouth. What do you observe now?
18. We blow for what all purposes?
19. What else can the hot air be used for?
20.How does air from the mouth help in cleaning spectacles?
Answer Key:
1.
Woodcutter
Stethoscope
Mian
8 to 16
Chulha
2. (b)Stethoscope
(d) 44
(a) Flute
(c) Running
3.
(a) Acoustic guitar
(b) Bagpipe
(c) Tabla
(d) Saxophone
(e) Maracas
(f) Trumpet
Musical instruments of options (a), (c) and (e) do not play by blowing air into them.
4. We can warm our hands by blowing on them in winters.
5. It feels cozy and comfortable.
6. Hot air is lighter than the surrounding cold air as there is more space between the molecules.
7.
8. A woodcutter is a person who cuts trees to supply wood to people.
9. The air we blow on the mirror is warm air, which when in contact with surrounding air cools down and turns into tiny water droplets.
10. Mian Blaishtiye was the curious little man in the story.
11. We blow on hot objects to make them a bit cooler.
12. We would burn our tongue and lips if we ate hot food without cooling them down.
13. The woodcutter blows on his cold hands in winter.
14. The woodcutter has to work throughout the year for his livelihood. Hence in winters he blows on his hands to warm up his hands to make him feel warm and cozy.
15. Blow hot, Blow cold was written by Dr. Zakir Hussain.
16. When we blow air on our hand keeping it close to our mouth, the air feels warmer than the surrounding air.
17. When we blow air on our hands, keeping it at a distance, the air doesn't feel warm, this is particularly because the warm air gets mixed up with surrounding cold air.
18. We blow to keep our hands warm, to cool down hot food and even to blow off the candles.
19. As we know hot air rises up, so it is also used in hot air balloons.
20. The air from our mouth contains moisture which when in contact with the surface of the spectacles, forms tiny droplets and helps us clean them.
Importance of Blow Hot Blow Cold Class 5 EVS Worksheet
This chapter introduces novel ideas to kids, which are extremely useful in our everyday lives.
The difference between warm, cold, hot, and freezing become clear to children through examples and explanations in this chapter.
Through practical examples, kids understand how an object turns clockwise or anti-clockwise based on the flow direction of air.
They also learn that in emergency situations like getting hit on the head, a cold or hot compress helps in bringing down the swelling. This can prepare them to take necessary action if such a situation arises.
Through the concept of breathing, kids also learn how their breath rate goes up and down before and after a strenuous activity like jumping.
Examples of Blow Hot Blow Cold Class 5 EVS Worksheet
Blowing has many purposes, and the examples in this chapter show students to explore all the different ways blowing is used in our lives.
Why do you blow air for the following activities?
Playing flute
Blowing birthday candles
Blowing on cold hands
Blowing on a toy that rotates
Draw the instrument that doctors use to hear the heartbeat.
Measure the chest of three children when they breathe in and breathe out and find out the difference.
A number of pictures of instruments are provided (trumpet, flute, violin, guitar, drum, saxophone,) and kids have to choose and colour those instruments which make a sound when we blow into them.
Blow hot blow cold MCQ questions:
We feel warm when we put on a blanket because:
The blanket is warm.
The blanket does not let air enter.
Our body is warm.
None of the above.
Interesting Facts About Blowing Air
If air is blown through a small opening in a fast manner, the air that comes out is cold.
If air is blown through a large opening in a slow manner, the air that comes out is hot.
If we place our hands close to our mouth, we feel hot air but if we move them away, the air feels colder.
The air coming out of our mouths does not differ in temperature, but it is the air in our surroundings that causes hot and cold phenomena.
The air in our atmosphere is always cooler than the air from our lungs.
Important Topics of Blow Hot Blow Cold Chapter
Understand the concept of blow hot blow cold through a story and various practical experiments.
Perform some experiments to find out how our breathing changes after an exercise.
Make a stethoscope of a rubber tube and listen to your heart rate.
Make whistles out of different objects like a toffee wrapper, cap of a pen, balloon, etc. and find out which one makes the loudest sound when you blow in it.
Get Your Free Copy of Hot and Cold Worksheet PDF Now
The concept of hot and cold through blowing is explained in an interesting manner so that kids understand as well as play around with this concept in many ways.
The blow hot blow cold Class 5 EVS worksheet Pdf is available to download for free so that you can keep it on your device and access it from anywhere anytime.
The Pdf is also available in a printable format which gives you the ease of access for a quick revision right before your exam.
Vedantu has an experienced team of experts who do extensive research to come up with content for Class 5 students. The PDF adheres to the latest CBSE curriculum and can guarantee you high marks in exams.
FAQs on Ncert Solutions Class 12 Micro Economics
1. What are some important short-answer questions from Chapter 15, 'Blow Hot, Blow Cold'?
For your exams, you should be ready to answer short questions like:
- What did the woodcutter do to warm his hands?
- Why did he blow on the hot potatoes?
- Which organ in our body helps us breathe?
2. Why did the woodcutter blow on his cold hands and also on his hot potatoes? How can the same breath be both hot and cold?
This is a key concept in the chapter. Our breath is not magical; its effect depends on the object's temperature. Our breath is warmer than our cold hands, so it transfers heat to them. However, our breath is cooler than boiling hot potatoes, so it helps to carry heat away from them, making them cool enough to eat.
3. What is the main scientific idea taught in the 'Blow Hot, Blow Cold' story?
The main scientific idea is that the air we exhale from our lungs has a consistent temperature. Whether this air warms something up or cools it down depends entirely on the relative temperature of the object we are blowing on. It demonstrates a simple form of heat transfer.
4. How can we use our breath in everyday life? Give two examples for warming and two for cooling.
We use our breath in many ways. Here are some examples:
- To Warm Things Up: We blow on our cold hands in winter or on a spectacle lens to clean it with the moisture from our warm breath.
- To Cool Things Down: We blow on a hot cup of tea or a spoonful of soup to make it cool enough to drink.
5. What important lesson or moral does the story of the woodcutter teach us?
The most important lesson from the story is that we should not be afraid of things we don't understand. Instead, we should be curious and try to find the scientific reason behind them. What seemed like magic to the tiny man (Mian Balishtiye) was just simple science for the woodcutter.
6. How does a doctor use a stethoscope, and how does it relate to this chapter?
A doctor uses a stethoscope to listen to the sounds inside our body, especially our heartbeat. This is related to the chapter because, just like our breath, our heartbeat is a vital sign of life. The stethoscope simply amplifies the sound of the heart, which the chapter encourages you to feel by placing a hand on your chest.
7. What are some likely long-answer or 3-mark questions from this chapter for the 2025-26 exams?
For higher marks, you might be asked to explain concepts in detail. A likely question would be, 'Explain with examples how the same breath can be used for both warming and cooling.' You would need to describe the woodcutter's actions for both his hands and the potatoes, explaining the process of heat transfer in each case.
