How do you convert Kelvin to Fahrenheit?

Question

5238 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-12-18T03:02:10

Convert into Celsius first, then from Celsius into Fahrenheit.

Kelvin is a derivative temperature of Celsius, therefore you must convert into Celsius first, before converting into Fahrenheit.

To convert Kelvin into Celsius, you simply add 273.15.

E.g.

#T_"C" = T_"K" + 273.15#

#=-273.15K + 273.15#

#=0#

#-273.15 K# is #0^o C#.

To convert Celsius into Fahrenheit, you have to multiply the Celsius temperature with #9/5#, then add #32#.

E.g.

#T_"F" = T_"C"(9/5)+32#

#=0(9/5)+32#

#=0+32#

#=32#

#0^o C# is #32^oF#.

Hope this helps :)

Answer 2 · 2016-12-18T03:07:55

By combining two formulas.

#""^@ "F" = 9/5("K") - 459.67#

Normally, we consider #""^@ "C"# going to #"K"# or the other way around:

#""^@ "C" + 273.15 = "K"#

#""^@ "F" = 9/5(""^@ "C") + 32#

You could use both formulas to do the conversion, or you could substitute one into the other and derive a new formula.

Since #"K" - 273.15 = ""^@ "C"#:

#""^@ "F" = 9/5("K" - 273.15) + 32#

With some simplification, we obtain the conversion formula from #"K"# to #""^@ "F"#:

#color(blue)(""^@ "F" = 9/5("K") - 459.67)#

Notice that this looks similar to the #""^@ "C" -> ""^@ "F"# conversion.

This demonstrates that the Fahrenheit scale has different intervals in comparison to the Celsius and Kelvin scales.