Class 5 EVS Chapter 15 introduces the concepts of— hot and cold. blowing air on different objects. breathing. heartbeat direction of airflow. The NCERT textbook (Looking Around) questions are answered in a simple and engaging manner. We also have related ‘Learning Concepts’, and interactive worksheets with solutions. Our ‘Learning Beyond’ segment caters to all the probable questions that the child might think out of curiosity. Download Chapter 15 Blow Hot, Blow Cold in the PDF format for free.
The NCERT Solutions EVS Class 5 EVS Chapter 15 - Blow Hot Blow Cold are tailored to help the students master the concepts that are key to success in their classrooms. The solutions given in the PDF are developed by experts and correlate with the CBSE syllabus of 2023-2024. These solutions provide thorough explanations with a step-by-step approach to solving problems. Students can easily get a hold of the subject and learn the basics with a deeper understanding. Additionally, they can practice better, be confident, and perform well in their examinations with the support of this PDF.
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Students can access the NCERT Solutions EVS Class 5 EVS Chapter 15 - Blow Hot Blow Cold. Curated by experts according to the CBSE syllabus for 2023–2024, these step-by-step solutions make EVS much easier to understand and learn for the students. These solutions can be used in practice by students to attain skills in solving problems, reinforce important learning objectives, and be well-prepared for tests.
Have you warmed your hands in winter by blowing on them when they are cold? How does it feel?
Yes, I have warmed my hands by blowing on them. It feels warm and comfortable.
[Students should mention their experience based on the above lines.]
Blow hard from your mouth onto your hands. How did you find the air from your mouth as compared to the air around? Was it hotter or cooler?
I found that the air blown from my mouth was warmer than the air around me.
[Students should mention their experience based on the above lines.]
Now put your hands at some distance from your mouth and blow again. Does the air from your mouth feel warm? Why?
When the hands are at a distance from my mouth, the air seems less warm. It happens because when the air travels for a distance, it gets mixed up with the surrounding air and becomes less warm.
[Students should mention their experience based on the above lines.]
Sonu was feeling very cold. He kept blowing on to his hands. Now think and write, which will be cooler—Sonu’s hands or his breath?
Sonu’s hand will be cooler.
Can you think of any other way in which you use the warmth from your breath?
Yes, we can use warmth from our breath in the following situations—
i) To soothe red eyes.
ii) To soothe minor bruises and injuries.
Fold a piece of cloth 3-4 times. Now bring it close to your mouth and blow hard on it. Did the cloth become warm?
Yes, the cloth becomes warm.
Balishtiye saw that the woodcutter was trying to cool the hot potatoes by blowing on them. What would have happened if he had eaten the potatoes without cooling them?
Eating hot potatoes would have burnt his tongue and mouth.
Have you ever burnt your tongue when you ate or drank something that was too hot? How do you cool some food when it is too hot?
Yes, I have often burnt my mouth while sipping hot tea and milk. I blow air to cool food when it is too hot.
[Students should mention their experience based on the above lines.]
If you were to cool these three hot things—dal, roti, rice—in which ways would you do so?
I would use the following methods to cool the above-mentioned things—
i) Dal: Keeping it in a wide flat container so that it cools quickly.
ii) Roti: Tearing it in pieces would cool it quickly, and it would allow the warm air to escape.
iii) Rice: It can be cooled by spreading it in an open vessel.
[Students should mention their experience based on the above lines.]
Mini tried to cool her tea by blowing on it. Which do you think will be hotter—Mini’s tea or the air she blew from her mouth?
Mini’s tea would be hotter than the air blown.
For what other things do you blow air from your mouth?
Some other activities which can be done by blowing air from the mouth are as follows—
i) Inflating a balloon
ii) Blowing off a candle
iii) Whistling
iv) Wiping spectacles
[Students should mention their experience based on the above lines.]
Make whistles of the things given below. Write in a sequence—from the loudest to softest whistle.
— Wrapper of a toffee
— A leaf
— A balloon
— The cap of a pen
— Any other thing
The sequence from loudest to softest whistle will be—
i) The cap of the pen
ii) By putting fingers in the mouth
ii) Wrapper of a toffee
iii) A balloon
iv) A leaf
Have you seen people playing different musical instruments like flute, dholak, been…guitar, mridang, etc. Can you recognise their sounds with your eyes closed? Find out more about these musical instruments. Collect their pictures too.
Yes, we can identify the sounds of these instruments even if our eyes are closed. The instruments are described below—
i) Flute: It is a type of wind instrument. It is made of bamboo and played by blowing air into it.
ii) Dholak: It is a type of percussion instrument. It is a hollow cylinder where a membrane of leather is tied at both ends. The sound is produced by beating the leather membrane.
iii) Been: It is a kind of wind instrument used by snake charmers. It is made of hollow dry pumpkin.
iv) Guitar: It is a type of string instrument. The metal strings attached to the wooden base are used to produce sound.