Units for temperature?
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Units for temperature?
When calculating from the specific heat capacity using the formula q=C(m) (delta T), do we use units for temperature as degree celsius or Kelvin?
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Re: Units for temperature?
I think you would use K, although since q = mc(delta T) is the change in temperature, the change itself would be the same number whether you use celsius or K. For example, if something changed from 0 to 2 celsius (which is 273 to 275 K), the delta T would still be 2 no matter what you use.
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Re: Units for temperature?
The specific heat refers to the increasing of energy in joules per unit of temperate. Both Kelvin and Celsius can be used as this unit of temperature. The unit of Kelvin means degree celsius + a constants (273.15). As a result, the units of Kelvin are the same as Celsius, but they are shifted up a scale with a value of 273.15.
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Re: Units for temperature?
Riya Sood 4G wrote:When calculating from the specific heat capacity using the formula q=C(m) (delta T), do we use units for temperature as degree celsius or Kelvin?
I believe you use celsius because the heat capacity (C in the equation) has units of J/(cg). Using the constant you are given, make sure that the units cancel. Depending on the constant, the units for temperature may very. On the equation sheet that Dr. Lavelle gave us the constant has units of C, so I would use C.
Re: Units for temperature?
I think that it can be either, its just a matter of making sure that your units are all compatible all the way throughout. I think Kelvin would be the more standard though
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Re: Units for temperature?
There is quite literally no difference between using Celsius or Kelvin in problems (such as these) where only change in temperature--not an absolute temperature--is involved. Whether you calculate the deltaT using Celsius or Kelvin will give you the exact same value since the temperature systems are on the same scale. So in these problems, use whatever units the temperature is given in, as it truly will not make a difference whether you use one or the other.
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Re: Units for temperature?
Either works, since a change in 1 degree Celsius is equivalent to a change in 1 Kelvin.
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Re: Units for temperature?
The change in heat per celsius is the same as the change in heat per kelvin, so you could use either.
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Re: Units for temperature?
You can use either Celsius Kelvin, but the units must be consistent throughout the equation, so the specific heat constant (for the specific material) must also be in the same units as the deltaT in the equation q=cmdeltaT.
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Re: Units for temperature?
When you are calculating for the specific heat you should be using Kelvins.
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Re: Units for temperature?
You can use either unit, but make sure you use the same units throughout the problem.
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