Module 2 Pretest Homework Packet Answers

Part G Temperature Conversion     5 points

The general formula for the conversion of temperatures on scale X to temperatures on scale Y is:

oY   =     Y units/ x units ( oX - RPx)   +   RPy

1.Write the formula for the conversion of Fahrenheit to Celsius:

oC  =  5 C units/ 9 F units [ oC – (-40)]  +   (-40)

or

oC  =  5 C units/ 9 F units (oC +40)  -  40

2. Write the formula for the conversion of Kelvin to Celsius:

oC  = K - 273

3. convert -196oC to oF

oF  =  9 F units/ 5 C units [ oC + 40)]  - 40

oF     =  9/5 (-196 + 40) – 40  = 9/5 (-156) – 40   =  - 280.5 -40  = -320.5  oF

4. convert -196oC to K

K  = oC + 273

K  = oC + 273 = -196 + 273  = 77 K

5. The Rankin scale uses a Fahrenheit unit, but assumes zero to be absolute zero.  If absolute zero on the Kelvin scale is zero and on Celsius scale is -273oC, calculate absolute zero on the Fahrenheit scale, then estimate the Freezing point of water on the Rankin scale.

(The BP water = 212 oF = 100 oC = 373K)

oF  =  9 Funits/ 5 Cunits [ oC + 40)]  - 40

oF     =  9/5 (-273 + 40) – 40  = 9/5 (-233) – 40   =  - 419.4 -40  = -459.4  oF

absolute zero on Rankin =  0 R equates to -459.6 oF therefore:

oR  =  1 Runits/ 1 Funits [ oF – (-459.4)]  +   0

oR  =  1 / 1 [  32oF – (-459.4)]  +   0 = 32 + 459.4 = 491.4 oF

Additional Homework  (not required) for your practice:

Corwin 7th edition:

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