1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why we would 32 in Celsius to Fahrenheit & Vice Versa. Please

  1. May 20, 2009 #1
    Why we would 32 in Celsius to Fahrenheit & Vice Versa. Please!!!!

    Hey fellows , please tell me why we add 32 to celsius to fahrenheit conversion and vice versa. According to my mind I derive C to F formula of my own. I do following.


    1)I look and choose same scale of F and C . The most obvious of which is freezing and boiling point. For F (32-212) and for C (0-100).


    2)Now to derive formula for C to F , i divided 180/100 =1.8 it means that if celsius then corresponding F is 1.8. So I now want to know how much is 37C in Fahrenheit then I multiplied it by 1.8*37=66.6 which is not true unless I add 32 to this. But why would I actually do that. Please explain.
     
  2. jcsd
  3. May 20, 2009 #2
    Re: Why we would 32 in Celsius to Fahrenheit & Vice Versa. Please!!!!

    You've correctly figured out the relative scales for F and C temperatures, i.e. the ratio of one degree C to one degree F, but since the two don't both start at the same zero point, you have to add 32 degrees, which is the amount of offset between them. In other words, if they both defined zero degrees to be the freezing point of water, but used their different scales, then you'd be fine, but since the Farenheit scale is offset by 32 degrees, you must account for that.

    Maybe it would help you to draw a plot of F degrees vs. C degrees. You could have a line parallel line to the F line that went through the origin - that would correspond to what you would get with no offset. But the correct F line is offset by 32.
     
    Last edited: May 20, 2009
  4. May 20, 2009 #3
    Re: Why we would 32 in Celsius to Fahrenheit & Vice Versa. Please!!!!

    Thanks guy. =)
     
  5. May 20, 2009 #4

    MATLABdude

    User Avatar
    Science Advisor

    Re: Why we would 32 in Celsius to Fahrenheit & Vice Versa. Please!!!!

    The Celsius scale was based on the freezing and boiling points of water. The Fahrenheit scale was based on the freezing point of a brine solution and the temperature of the human body:
    http://en.wikipedia.org/wiki/Fahrenheit
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Why we would 32 in Celsius to Fahrenheit & Vice Versa. Please
  1. Celsius = Fahrenheit (Replies: 4)

Loading...