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प्रश्न
To expel hot air out of the kitchen, ‘A’ has an exhaust fan fitted on the window of her kitchen and ‘B’ has a similar exhaust fan fitted on the wall near the ceiling of her kitchen. Which of the exhaust fan will expel the hot air more effectively? Explain why?
उत्तर
B’s exhaust fan will expel the hot air more effectively because hot air rises up, so being at a greater height than A’s exhaust fan, the volume of air that will reach B’s exhaust fan will be more.
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संबंधित प्रश्न
Following are precautions one must take in case a storm is accompanied by lightning.
(i) Do not take shelter under a tree.
(ii) Do not take shelter under an umbrella with a metallic end.
(iii) Do not take shelter in open garages, storage sheds, etc.
(iv) Do not take shelter in a bus in the open.
Which one of these is not correct?
Air around us exerts __________ .
The moving air is called _________ .
State whether the following statement is True or False:
Warm air is lighter than cool air.
Match Column I with Column II. There can be more than one match.
| Column I | Column II | ||
| (a) | on heating air | (i) | descends |
| (b) | on cooling air | (ii) | expands |
| (iii) | contracts | ||
| (iv) | rises | ||
Describe an activity to demonstrate that warm air is lighter than cool air
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