THE FAHRENHEIT SCALE

In much of the English-speaking world, and especially in the United States, the Fahrenheit temperature scale (°F) is used by laypeople. A Fahrenheit degree is the same size as a Rankine degree. However, the scale is situated differently. The melting temperature of pure water ice at sea level is +32°F, and the boiling point of pure liquid water is +212°F. Thus, + 32°F corresponds to 0°C, and +212°F corresponds to +100°C. Absolute zero is approximately -459.67°F.
The most common temperature conversions you are likely to perform involve changing a Fahrenheit reading to Celsius, or vice versa. Formulas have been developed for this purpose. Let F be the temperature in °F, and let C be the temperature in °C. Then, if you need to convert from °F to °C, use this formula:
F = 1.8C +32
If you need to convert a reading from °C to °F, use this formula:
C = 5/9(F - 32)
While the constants in these equations are expressed only to one or two significant figures (1.8, 5/9, and 32), they can be considered mathematically exact for calculation purposes.
Figure 1 is a nomograph you can use for approximate temperature conversions in the range from -50°C to +150°C.
When you hear someone say that the temperature at the core of a star is 30 million °F, the Rankine reading is about the same, but the Celsius and Kelvin readings are only about 5/9 as great.

Fig. 1. This nomograph can be used for approximate conversions between temperatures in °F and °C.

مواضيع ذات صلة

الديناميكا الحرارية الجزيئية

توزيع بولتزمان

العلاقات بين الخواص

القانون الثالث للديناميكا الحرارية

الطاقة الحرة

القانون الثاني للديناميكا الحرارية

القانون الأول للديناميكا الحرارية

Order and entropy

Irreversibility

The Clausius-Clapeyron equation

Internal energy

Entropy