Heat Capacity and Energy supplied

AI Thread Summary
The discussion revolves around calculating the energy required to heat a volume of air using the formula E=mc(delta T/delta t). The user calculated a heating rate of 12.56J per second for a 16K temperature rise over 10 hours for 24m3 of air, which they felt was too high. There was confusion regarding the inclusion of (delta T/delta t) in the formula, as it indicates energy per second rather than total energy. Participants clarified that the original question was valid for self-study rather than homework. The conversation highlights the importance of understanding the context and correct application of physics formulas.
nina
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I'm stuck on some basic physics...

I'm using the formula E=mc (delta T/delta t) where E is energy, m is mass, c is specific heat, T is temperature and t is time, to calculate the energy used in heating a volume of air to a certain temperature.

Assuming that pressure is of that at sea level, I come up with a rate of heating of 12.56J per second, for a 16K rise in temperature over 10 hours, for a volume of air of 24m3.

This seems a little high, what did I do wrong?
 
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we have just been told that E=mc*deltaT, in both physics and chemsitry...?

where did you get the (deltaT/deltat) ?EDIT: ah ha! i see where the discrepancy lies... you are working out energy per second. sorry.
 
nina said:
I'm stuck on some basic physics...

I'm using the formula E=mc (delta T/delta t) where E is energy, m is mass, c is specific heat, T is temperature and t is time, to calculate the energy used in heating a volume of air to a certain temperature.

Assuming that pressure is of that at sea level, I come up with a rate of heating of 12.56J per second, for a 16K rise in temperature over 10 hours, for a volume of air of 24m3.

This seems a little high, what did I do wrong?
That's about the same number I get...but next time:

1. Please post such questions in the Homework & Coursework subforums, and
2. Use the template provided (and write down the original question EXACTLY as it was given to you).
 
Gokul43201 said:
That's about the same number I get...but next time:

1. Please post such questions in the Homework & Coursework subforums, and
2. Use the template provided (and write down the original question EXACTLY as it was given to you).

Thanks, but it's not homework! I'm trying to work it out for myself for another project, needed to check the answer before I went forward with the work!

That IS the original question, shows why I shoudnt be a teacher!
 
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