degrees Fahrenheit (F) to degrees Celsius (C) conversion

What is degrees Fahrenheit?

Degrees Fahrenheit ($^\circ F$) is a unit of temperature measurement commonly used in the United States and a few other countries. It's part of the Fahrenheit scale, a temperature scale developed by physicist Daniel Gabriel Fahrenheit in the early 18th century.

History and Origin

• Daniel Gabriel Fahrenheit: The scale is named after him, a German physicist, instrument maker, and glassblower.
• Early Thermometers: Fahrenheit made significant improvements to the accuracy and reliability of thermometers, which were still relatively new at the time.
• Original Zero Point: Fahrenheit originally defined 0 $^\circ F$ as the freezing temperature of a brine solution made from water, ice, and ammonium chloride salt.
• Water's Freezing Point: He initially set the freezing point of pure water at 32 $^\circ F$ and the human body temperature at 96 $^\circ F$ (later refined to 98.6 $^\circ F$).

Defining Points

The Fahrenheit scale is defined by two fixed points:

• Freezing Point of Water: 32 $^\circ F$
• Boiling Point of Water: 212 $^\circ F$ (at standard atmospheric pressure)

This means there are 180 degrees between the freezing and boiling points of water on the Fahrenheit scale.

Conversion Formulas

• Celsius to Fahrenheit:

  $^\circ F = (^\circ C * \frac{9}{5}) + 32$

• Fahrenheit to Celsius:

  $^\circ C = \frac{5}{9} (*^\circ F - 32)$

Real-World Examples

• Body Temperature: Normal human body temperature is approximately 98.6 $^\circ F$.
• Room Temperature: Comfortable room temperature is often around 72 $^\circ F$.
• Baking Temperatures: Many baking recipes use Fahrenheit, such as 350 $^\circ F$ for cakes or 400 $^\circ F$ for roasting vegetables.
• Weather Reports: In countries that use Fahrenheit, weather forecasts provide temperatures in degrees Fahrenheit. For example, a hot summer day might be 95 $^\circ F$, while a cold winter day could be 20 $^\circ F$.

Notable Facts

• Usage: While most countries use the Celsius scale for everyday temperature measurements, Fahrenheit remains common in the United States, the Bahamas, Belize, the Cayman Islands, and Liberia.

• Kelvin Scale Relationship: Although less direct than with Celsius, Fahrenheit can also be related to the Kelvin scale:

  $K = \frac{5}{9} (*^\circ F - 32) + 273.15$

What is degrees celsius?

Let's explore the world of degrees Celsius, a fundamental unit of temperature measurement. This explanation will cover its definition, history, conversion formulas, and real-world applications.

Definition of Degrees Celsius

The degree Celsius ($^\circ C$) is a unit of temperature on the Celsius scale, a temperature scale originally designed so that the freezing point of water was $0 ^\circ C$ and the boiling point was $100 ^\circ C$ at standard atmospheric pressure. It is an SI derived unit.

History of the Celsius Scale

The Celsius scale was invented by Swedish astronomer Anders Celsius in 1742. Originally, Celsius defined his scale "upside down": zero represented the boiling point of water, and 100 represented the freezing point. It was later reversed to its current form by either Jean-Pierre Christin in 1743 or Carolus Linnaeus in 1744.

Conversion Formulas

Here are the key formulas to convert Celsius to other common temperature scales:

• Celsius to Fahrenheit:

  $$^\circ F = \left(^\circ C \times \frac{9}{5}\right) + 32$$

• Celsius to Kelvin:

  $$K = ^\circ C + 273.15$$

• Fahrenheit to Celsius:

  $$^\circ C = \frac{5}{9}(^\circ F - 32)$$

Celsius and Thermodynamics

Celsius plays a key role in thermodynamics. The absolute zero temperature (0 Kelvin), where all molecular motion ceases, is equivalent to -273.15 $^\circ C$.

Real-World Examples

• Body Temperature: Normal human body temperature is approximately 37 $^\circ C$.
• Room Temperature: Comfortable room temperature is often around 22-25 $^\circ C$.
• Cooking: Water boils at 100 $^\circ C$ at sea level, crucial for cooking and sterilization.
• Weather: Daily temperatures are commonly reported in Celsius in many parts of the world. For instance, a pleasant summer day might be 28 $^\circ C$.
• Freezing Point: Water freezes at 0 $^\circ C$.

Interesting Facts

• The Celsius scale is widely used around the world, especially in scientific contexts.
• The size of one degree Celsius is the same as the size of one Kelvin. Only the zero point is different.

Notable Associations

• Anders Celsius: The Swedish astronomer who originally devised the scale. His work laid the foundation for a standardized temperature measurement system.

For further reading, you might find the NIST Temperature Scale FAQ helpful.