How to Determine if Temperature Increase is Due to Work or Heat?

AI Thread Summary
The discussion centers on distinguishing between work done and heat generated in a thermally insulated system. When shaking water in a container, the temperature increase results from work done rather than heat added, as energy can be transferred through mechanical means. Similarly, in the case of a paddle connected to a movable block, the temperature rise is attributed to work done, reinforcing the idea that mechanical work can convert to thermal energy. This concept aligns with Joule's experiments demonstrating the conversion of mechanical work into heat. Ultimately, both scenarios illustrate that temperature increases in these contexts stem from work rather than heat flow.
pardesi
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suppose a certain process is carried out on a system which say heats up the system the how do we decide that that's due to work done or heat released.
for example suppose i put water in an thermally insulated container and shake it and it's temp. increases then is it due to heat or work done
 
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Once the energy is in the form of heat there is no difference in how the heat was initially generated.
 
but my book says it's work done and not heat generated
 
Heat flow requires a temperature difference. The issue is not "is thermal energy increased?"--of course it is. You can increase internal energy by doing work or by adding "heat". When you shake the water bottle, the increase in temperature is due to the work you've done.
 
yes this is what i thought.Also what about this case
there is a paddle immersed in water fixed within which is connected to a movable block through a fixed pulley When the block moves the temp of the system rises is it work done or heat released .I think work done because the same reason as above .
Would like to know ur answers
 
pardesi said:
Also what about this case
there is a paddle immersed in water fixed within which is connected to a movable block through a fixed pulley When the block moves the temp of the system rises is it work done or heat released .I think work done because the same reason as above .
Would like to know ur answers
Sure, that's a similar situation: the temperature increase is due to work done, not "heat" added. In fact, that paddle experiment was used by Joule to first show that mechanical work can be converted to "heat".
 
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