Ask A Scientist
Physics Archive
Index Key: PHY060
Author: philip
Subject: Why is drying dishes in warm water easier than...
Text: Why is it easier to dry dishes washed in warm water then cold
water?
Response #: 1 of 2
Author: Sam Bowen
Text: I believe it is due to the strong temperature dependence of the
evaporation rate. The warmer water molecules are more likely to leave the
hotter object for the cooler air.
Response #: 2 of 2
Author: Arthur Smith
Text: Well, I guess I usually just let dishes dry in the dish
drainer... What happens when you dry them with a cloth is that you soak up
almost all the water onto the cloth, but the cloth has trouble picking up that
last little bit because you just got the cloth wet drying the dish. So,
whether the dish was washed in hot or cold water, if you wipe it once with a
cloth, you will have a semi-wet cloth and a still-moist dish. Now, if the
water was quite hot, what you have just done is spread that hot water over
quite a large surface area (the cloth, and the small amount remaining on the
dish) and it can evaporate pretty fast. Several wipes, and you are done, and
the cloth still is not that wet. But cold water is not going to evaporate
just like that, and it may not even want to get into the air at all. The
other possible explanation, of course, is that cold water sticks to dishes
better than hot water.
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