Units
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Units
Hello,
Could someone please tell me what is wrong with these units. I hit the * and then inserted temp units (F)
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That's Prime... Note that many of the temperature units are functions rather than 'simple' units, due to the fact that conversion requires more than simple multiplication with a constant.
Success!
Luc
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so what do I do? How do I insert units in alpha (co-eff of thermal expansion in/in*degF)
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You need the delta temp, which is available in the temperature units.
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What you want is change in °F (Δ°F), not °F.
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OK.
But then why does it produce an error message: "This value must be a scalar or a matrix".
???????
Luc
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Short answer:
Because of poor error handling.
Slightly longer answer:
Because (as you noted) °F is a function. You can't multiply by °F for the same reason you can't multiply by any other function (numerically). You can only multiply by a scalar or matrix. The °F function can only be applied to a scalar or matrix, not multiplied by one.
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Better use here R and K not F and C
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Δ°F = R and Δ°C = K
The difference is merely display.
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I asked my colleague from NIST why you have R in the unit of entropy, and in thermal conduction unit F. He answered that it is easier to change the US Constitution than to teach American engineers to use R in the thermal conductivity unit, rather than F.