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प्रश्न
Have you seen someone blowing on their spectacles to wipe them clean? How does the air from the mouth help in cleaning the spectacles?
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उत्तर
The air blown from the mouth is hot and the glass of the spectacles is comparatively colder. The hot air we breathe out contains water vapours which turn into tiny droplets of water when it comes in contact with the colder glass. This makes the glass moist and hazy.
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संबंधित प्रश्न
Miya Balishtiye was confused when he saw the woodcutter blowing on his cold hands to make them warm and on the hot potatoes to cool them.
- Have you warmed your hands in winter by blowing on them when they are cold? How does it feel?
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?
Picture 2 - Sonu was feeling very cold. He kept blowing onto his hands. Now think and write, which will be cooler – Sonu’s hands or his breath?
Can you name some things which produce melodious or pleasing sounds when we blow into them?
Count how many times in one minute do you breathe in and breathe out.
Jump 30 times. Did you feel breathless?
What was the difference in your count before and after jumping?
While playing, Amit hit a wall. His forehead was swollen. Didi immediately folded a scarf (4-5 times), blew on it, and kept it on Amit's forehead. Why do you think didi did this?
We blow to cool hot things as well as to warm them. Give examples of each.
Can you understand from the movement of the snake - if the air is moving upwards or downwards?
