Sunday, 31 May 2015

homework and exercises - Suppose we do this experiment in a vacuum, will the small pieces of paper behind the bottle be blown?



Put a lit candle behind abottle. If you blow on the bottle from the opposite side, the candle may goout, as if the bottle was not there at all. Explain the phenomenon.


My vacuum here refers to the space beyond the atmosphere.


enter image description here


As shown in the figure, the reason why the candle is blown is that there is atmospheric pressure, which will press the blown air on the surface of the bottle and make it move along the surface of the bottle, so it will blow the candle behind the bottle as if the bottle does not exist.


There is no atmosphere or atmospheric pressure in the vacuum, so the blown air will no longer move along the surface of the bottle, so it will not blow the small pieces of paper behind the bottle.




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