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Anonymous at Wed, 10 Jul 2024 03:57:31 UTC No. 16275560
I'm doing some homework with thermodynamics, i had to find the heat capacity ratio of air and i got 1,322 ± 0,038. The tabulated value is 1.403. How can I justify that my result is less than expected?
Are there any conditions of the enviroment that can change the value of the coefficient? The only thing that came to my mind was air humidity.
Anonymous at Wed, 10 Jul 2024 06:37:47 UTC No. 16275658
>>16275560
1.403/1.322 is about 1.06 so about 6% Variationen from the tabulated value which should be fine in my view.
Anonymous at Wed, 10 Jul 2024 06:42:30 UTC No. 16275665
>>16275658
i know that it is fine, but i have to write a conclusion and i want to address possible reasons as to why is it smaller than the real value. Not a problem with the result, just need to fill some paragraphs.
Anonymous at Wed, 10 Jul 2024 06:54:51 UTC No. 16275674
>>16275665
Ah. Yea probably humidity maybe dust
Anonymous at Wed, 10 Jul 2024 08:32:35 UTC No. 16275732
>>16275665
You made a mistake
Anonymous at Wed, 10 Jul 2024 08:33:01 UTC No. 16275734
>>16275560
density changes away sea level. Also, calculate the error range of your instruments which probably accounts for it.
Anonymous at Wed, 10 Jul 2024 20:56:33 UTC No. 16276515
>>16275665
Convert your percentage in log10.
The error should be even closer to 0 if (a+error)/b is close to 1.
You said 6%, so it's 0.06 + 1 = 1,06
log10 (1,06) = 2,5% in log10 that's way better.
Trust me, I'm an Engineer :)
Anonymous at Thu, 11 Jul 2024 11:35:05 UTC No. 16277177
>>16275560
moisture content, pressure and temperature that day. I think more to do with methodology and tools as well because those can gain and lost heat or pressure as you are measuring them and if they are calibrated right first. If you are using the OP picture to get kappa from two separate experiments for cp and cv then both has to be examined as well.
You can also use a piston to see how it responds to adiabatic process: PV^k=T
Anonymous at Thu, 11 Jul 2024 11:37:19 UTC No. 16277180
>>16277177
*pv^k=constant
Anonymous at Thu, 11 Jul 2024 11:51:39 UTC No. 16277197
>>16275658
You're not a scientist. Quantifying his data like that is WRONG. His error bound suggests his value is inconsistent with the accepted value ( p < 0.05) or consistent with the accepted value ( p < 0.01).
Op consider the following: what the fuck does your error mean if this 6% has any significance?
Anonymous at Thu, 11 Jul 2024 23:56:58 UTC No. 16278028
>>16277177
Actually that's what i did, i used an adiabatic process. Didn't use Cv or Cp