How do you convert BTU/lbF into J/kgK?

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To convert BTU/lbF into J/kgK, it is essential to understand the difference between a temperature difference and an absolute temperature. The conversion involves recognizing that a 1°F temperature difference corresponds to a 5/9 K difference, not 1 K. The correct formula for the conversion is 1 BTU/lbF = 1055 J / (1/2.2046 kg) * (5/9 K). After applying this adjustment, the expected result aligns with the specific heat of water, which is 4186 J/kgK. This clarification resolves the initial confusion regarding the temperature scale.
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I know 1BTU = 1055J
1lb = 1/2.2046 kg
1 F = 255.928 K

then 1 BTU/lbF should be 1055/(1.2046)*255.928. But I get 9 plugging this in
the value is suppose to be 4186 J/kgK. this is the specific heat of water
 
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jamesfirst said:
I know 1BTU = 1055J
1lb = 1/2.2046 kg
1 F = 255.928 K

then 1 BTU/lbF should be 1055/(1.2046)*255.928. But I get 9 plugging this in
the value is suppose to be 4186 J/kgK. this is the specific heat of water
You've made a goofy mistake here. You're confusing a 1 degree F temperature difference with a temperature of 1° F.

On the Fahrenheit scale, there are 180 degrees separating the F.P. of water and its B.P. On the Kelvin scale, there are 100 degrees between the same two temperatures.
Thus, a temperature difference of 1°F = a temperature difference of 100 / 180 = 5/9 °K.

Try again to make your conversion.
 
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hey it works!
thanks. I've been confusing it with the temperature Fahrenheit the whole time ...
 
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