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[Phy] heat capacity question please help

1. The rate of heat transfer is directly proportional to the temperature difference
2. When the container has a smaller heat capactiy, even the same amount of energy is inputted,
     the temperature of the container will rise quicker and attain a very similar temperature with the water
     i.e. rate of heat transfer will become very small very quickly
     -->the heat lost to the container will be smaller afterwards.
By the way, please note that adsorb and absorb are two different words with two difference meanings.
   
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¤Þ¥Î:
­ì©«¥Ñ suking2014 ©ó 2016-10-9 03:57 PM µoªí
¦ý«Ysmaller heat capacity ­ø«Y·|increase heat loss to surroundings meh? ´N¦n¦üµoªw½¦ªMvsÅKªMËÝ
Firstly, expanded polystyrene cup (µoªw½¦ªM) has a smaller rate of heat loss to surrounding is because it is a poor conductor while metal cup is a good conductor.
(Or you may explain it by the shiny surface of metal cup which gives rise to a better emitter of radiation)

At least in DSE, we do not assume a direct relationship between heat capacity and heat loss to surrounding.

Secondly, the container is put in the oven, where the temperature inside the oven is always higher than the temperature of water
otherwise, water will not gain heat energy.
Therefore, there is no heat loss to surrounding in this case.
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­ì©«¥Ñ suking2014 ©ó 2016-10-10 05:47 PM µoªí

thanks,  ¦ý«Yafter the beaker being taken out from the oven, Ê\­nÊ\­n¥Î·Å«×­p¶qwater ge·Å«×, Ëݳ£­nµ¥¤@¬q®É¶¡¥ý¶q¨ìwaterûHfinal temperature (§A¥Î·Å«×­p©ñ¸¨100«×ûH¤ô³£­nµ¥´X¤Q¬í ·Å«×­p¥ý·|show100C ga ...
Please note that there is no direct relationship between heat capacity and rate of heat loss to the surrounding.
As I havbe mentioned, why a metal cup has a higher rate of heat loss is because of its shiny surface, but not its small heat capacity.
Lowering the heat capacity is not necessarily changing the material being used, like she can use a smaller beaker.
In this case, same material but smaller contact surface area with air-->smaller heat lost to the sorrounding, but it has a smaller heat capacity as its mass decreases.

You are using a wrong concept to derive a wrong conclusion.

Also, we indeed have a practice to ignore the time for measuring the temperature, unless it is specified by the question.
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