Units

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Lindsey Chheng 1E
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Joined: Fri Aug 30, 2019 12:16 am

Units

Postby Lindsey Chheng 1E » Tue Jan 28, 2020 10:36 pm

Why can the units for this chapter be either Kelvin or Celsius? Why are they interchangeable?

Caitlyn Tran 2E
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Joined: Fri Aug 09, 2019 12:15 am

Re: Units

Postby Caitlyn Tran 2E » Tue Jan 28, 2020 10:40 pm

Kelvin is just the degrees Celsius plus 273.15. However, one degree change in Kelvin is equal to one degree change in Celsius. For this reason, I think we can interchange them since we are mainly focused on the change in temperature rather than what the temperature actually is. Hope this helps!

Subashni Rajiv 1K
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Joined: Wed Sep 18, 2019 12:16 am

Re: Units

Postby Subashni Rajiv 1K » Tue Jan 28, 2020 11:02 pm

The change in temperature remains a constant regardless of what temperature unit is used. It's important to keep temperature units the same for each problem.

AlyshaP_2B
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Joined: Wed Sep 18, 2019 12:19 am

Re: Units

Postby AlyshaP_2B » Tue Jan 28, 2020 11:40 pm

The two are interchangeable here because we only look at temperature in terms of how it changes, and one unit kelvin is equivalent to one unit celsius.

Ellis Song 4I
Posts: 102
Joined: Thu Jul 11, 2019 12:17 am

Re: Units

Postby Ellis Song 4I » Wed Jan 29, 2020 11:28 pm

The temperature is interchangeable because Kelvin and Celsius are to the same scale. So one degree change of Celsius is one degree change in Kelvin and vice versa

Leonardo Le Merle 1D
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Joined: Wed Feb 27, 2019 12:16 am

Re: Units

Postby Leonardo Le Merle 1D » Thu Jan 30, 2020 10:12 am

°C = K + 273.15; there is no multiplication involved and thus the scale is proportional.

Bryce Barbee
Posts: 103
Joined: Wed Sep 18, 2019 12:20 am

Re: Units

Postby Bryce Barbee » Thu Jan 30, 2020 10:40 am

This is because we are only looking at the changes in each and because both have the same step size, it does not matter which is used.

Brandon Valafar
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Re: Units

Postby Brandon Valafar » Thu Jan 30, 2020 11:49 am

K=273.15+C, so they are interchangeable.

Tiffany_Chen 2K
Posts: 106
Joined: Fri Aug 30, 2019 12:15 am

Re: Units

Postby Tiffany_Chen 2K » Thu Jan 30, 2020 2:13 pm

Agreeing with the above comments, here is also the proof:

K=C+273.15
K1-K2=C+273.15-(C+273.15)
K1-K2=C1-C2

Ayushi2011
Posts: 101
Joined: Wed Feb 27, 2019 12:17 am

Re: Units

Postby Ayushi2011 » Thu Jan 30, 2020 3:51 pm

We record temperature in terms of how it changes, change in a celsius is same as a change in a kelvin.

ValerieChavarin 4F
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Joined: Wed Sep 18, 2019 12:18 am

Re: Units

Postby ValerieChavarin 4F » Thu Jan 30, 2020 4:02 pm

0°C= 273.15 K. When calculating change in temp, if you have 283.15K-276.15K or 10°C-3°C, the change in temperature is essentially the same.

Uisa_Manumaleuna_3E
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Joined: Wed Sep 21, 2016 2:56 pm

Re: Units

Postby Uisa_Manumaleuna_3E » Thu Jan 30, 2020 7:27 pm

It is a little confusing because we know Kelvin and Celsius to be different, but just remember that a majority of the calculations of temperature we do in this section are just asking for the CHANGE OF TEMPERATURE. Temp change the same way in Celsius and in Kelvin, by degrees. So it doesn't really hurt anything to say that, for discussion's sake, kelvin and celsius are synonymous.

Betania Hernandez 2E
Posts: 107
Joined: Fri Aug 02, 2019 12:15 am

Re: Units

Postby Betania Hernandez 2E » Thu Jan 30, 2020 9:47 pm

They are interchangeable because the change in temperature is the same whether you use Celsius or Kelvin. The change in degrees Celsius is the same as the change in degrees Kelvin.

Robert Tran 1B
Posts: 118
Joined: Thu Jul 11, 2019 12:15 am

Re: Units

Postby Robert Tran 1B » Thu Jan 30, 2020 9:54 pm

Since this chapter mostly deals with changes in temperatures, it does not matter whether Kelvins or Celsius are used because they are scaled the same.

Leslie Almaraz 4G
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Joined: Fri Aug 02, 2019 12:16 am

Re: Units

Postby Leslie Almaraz 4G » Fri Jan 31, 2020 6:05 pm

This is because they are both scaled the same. However, if this is still confusing try just using Kelvin.

Orrin Zhong 4G
Posts: 51
Joined: Sat Jul 20, 2019 12:16 am

Re: Units

Postby Orrin Zhong 4G » Fri Jan 31, 2020 6:25 pm

When calculating change in temperature, you can use either Celsius or Kelvin because Celsius = Kelvin + 273. Therefore, when you subtract two Celsius temperatures, they the +273 will cancel out and will equal the different between those two temperatures as Kelvin.

Ying Yan 1F
Posts: 101
Joined: Fri Aug 02, 2019 12:16 am

Re: Units

Postby Ying Yan 1F » Fri Jan 31, 2020 9:52 pm

It is probably interchangable because we usually only need the change in temperature, and regardless of whether the temperature is in Kelvin or in Celcius, the amount that changed will still be the same.


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