點解hot air會係地面?

Ranessa

2009-04-10 9:27 pm

"less dense substances flora on the denser ones"
hot air is less dense and cold air is denser

咁點解earth surface上面會係hot air而唔係cold air?
唔係應該cold air係地面架咩
有人話係因為地面吸熱.咁又係點解呢?

請回答用英文

回答 (2)

天同

2009-04-11 9:08 pm

✔ 最佳答案

The saying that "less dense substances float on dense substances" is ony true when the substances are in a closed system without energy input into it.
The earth atmosphere is not a closed system, it is constantly heated NON-UNIFORMLY by solar radiation. Hot air in the atmosphere does rise and cold air sinks. This produced high and low regions on earth surfaces and sets up air movement. Such circulation of air in the atmosphere produced the various weather conditions that we experience in our lives, such as land and sea breezes, monsoons, or typhoons.

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2009-04-11 1:39 am

乜唔係關密度事咩?

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