This document discusses different temperature scales and how to convert between them. It explains that Celsius, Fahrenheit and Kelvin are common temperature units, with Celsius used in the metric system, Fahrenheit in the Imperial/English system, and Kelvin as the SI unit. Formulas are provided to convert between Celsius, Fahrenheit, Kelvin and Rankine. Examples demonstrate using the formulas to perform conversions between different temperature scales.

1. SUBTITLE

2. Temperature is the measurement of the degree of hotness or coldness of
an object or environment. The unit used in the Metric system is Celsius (°C),
Fahrenheit (°F) for English or Imperial system, and Kelvin (K) for SI unit.
Celsius was named after the Swedish Astronomer Anders Celsius (1701-
1744). In Celsius, the freezing point of water is 0 degrees and its boiling point is
100 degrees. Fahrenheit was named after the German physicist Gabriel
Fahrenheit (1686-1736). In Fahrenheit , the freezing point of water is 32 degrees
and its boiling point is 212 degrees.
To convert one unit of temperature to the other, we have the following
formulas:
Fahrenheit to Celsius: Celsius to Fahrenheit:
C =
5
9
(F - 32) F =
9
5
C + 32

3. Kelvin is one of the 7 units in the International System of Units (SI). Kelvin
was named after an engineer and physicist William Thomson, 1st Baron Kelvin
(1824-1907). On the other hand, Rankine was named after an engineer and
physicist Willliam John Macquorn Rankine who proposed it in 1859. We have the
following formulas relating Kelvin to Celsius and Rankine to Fahrenheit.
Celsius to Kelvin: Kelvin to Celsius:
K = C + 273 C = K – 273
Fahrenheit to Rankine Rankine to Fahrenheit
R = F + 460 F = R - 460

4. Example 1.
How many °C are there in 58 °F?
Example 2.
What is the temperature of -40 °C
in Fahrenheit?
C =
5
9
(F - 32)
C =
5
9
(58 - 32)
C =
5
9
(26)
C =
130
9
= 14.44 °C
F =
9
5
C + 32
F =
9
5
(-40) + 32
F =
−360
5
= -72 + 32
= -40 °F
Celsius and Fahrenheit have equal
temperatures at -40°, that is -40 °C = -40 °F

5. Example 3.
An object’s temperature is 300
Kelvin. What is the temperature
in degree Celsius?
Example 4.
Wow many degrees Celsius are
there in 512 Rankine?
C = K – 273
= 300 – 273
= 27
The temperature of the object is 27 °C.
F = R – 460
F = 512 – 460
= 52 °F
Convert 52 °F in Celsius.
C =
5
9
(F - 32)
C =
5
9
(52 - 32)
C =
5
9
(20) = 11.11 °C