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Mathcad prime 4.0 issue with °F units

AL_9913769
5-Regular Member

Mathcad prime 4.0 issue with °F units

I'm subtracting 2 temperatures. But Mathcad gives an unexpected answer:

AL_9913769_1-1621269790902.png

ΔT should equal 280°F.

 

3 REPLIES 3
LucMeekes
23-Emerald III
(To:AL_9913769)

There are two types of temperature units in Prime, absolute and relative. You're using the absolute Fahrenheit units. This means that every temperature is converted to absolute temperature in kelvin, then subtracted, then the result is converted back to Fahrenheit because you requested the result to be Fahrenheit.

You should use Delta°F instead of °F for the result. See ttokoro's examples below.

 

Success!
Luc

ttokoro
20-Turquoise
(To:AL_9913769)

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@AL_9913769 wrote:

I'm subtracting 2 temperatures. But Mathcad gives an unexpected answer:

AL_9913769_1-1621269790902.png

ΔT should equal 280°F.

 


The 350°F are an absolute temp, but the 70°F are a relative temp.

 So IMHO the appropriate approach would be

Werner_E_0-1621636094411.png

 

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