- #1
Aleoa
- 128
- 5
As Feynman says, talking about a liquid in a container :
"So the liquid gradually cools if it evaporates. Of course, when a molecule of vapor comes from the air to the water below there is a sudden great attraction as the molecule approaches the surface. This speeds up the incoming molecule and results in generation of heat.
So when they leave they take away heat; when they come back they generate heat."
And then:
"If we blow on the water so as to maintain a
continuous preponderance in the number evaporating, then the water is cooled.".
I haven't understood this last sentence. It seems counter-intuitive because, as previous said, a molecule that go from the air to the liquid get accellerated ( so become more hot)
"So the liquid gradually cools if it evaporates. Of course, when a molecule of vapor comes from the air to the water below there is a sudden great attraction as the molecule approaches the surface. This speeds up the incoming molecule and results in generation of heat.
So when they leave they take away heat; when they come back they generate heat."
And then:
"If we blow on the water so as to maintain a
continuous preponderance in the number evaporating, then the water is cooled.".
I haven't understood this last sentence. It seems counter-intuitive because, as previous said, a molecule that go from the air to the liquid get accellerated ( so become more hot)