Sunday, February 7, 2010

When hot coffee is poured into a mug, all the heat the coffee loses is absorbed by the mug. true or false?

pls, help.. i'm confuse... thanksWhen hot coffee is poured into a mug, all the heat the coffee loses is absorbed by the mug. true or false?
false, most of the heat leaves as vapor.When hot coffee is poured into a mug, all the heat the coffee loses is absorbed by the mug. true or false?
False...much of the heat is transferred to the cooler air above the liquid.
false, like the last guy said the heat will be mainly transferred to the cooler air above it along with some moisture, also out of the heat that does hit the cup some of that is reradiated out and not held by the cup anymore
False.





When you pour hot coffee into a mug, there will be a sudden drop in temperature as heat is transferred from the coffee into the mug. As the mug heats up, the rate of transfer decreases.





Two other ways heat is lost are:





Evaporation of the coffee. That's related to the ';steam'; you see coming off the coffee in cold weather. It cools the coffee just like evaporation of sweat cools you on a hot day. The ';steam'; is not technically steam, it is condensed water vapor similar to a cloud.





Transfer of heat to the air by conduction and convection. The coffee warms the air above it.

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