degrees Rankine (R) to degrees Celsius (C) conversion

What is degrees rankine?

Degrees Rankine ($^\circ R$) is a thermodynamic (absolute) temperature scale named after the Scottish physicist and engineer William John Macquorn Rankine, who proposed it in 1859. It's primarily used in engineering, particularly in the United States. Let's delve into its details.

Definition and Origin

The Rankine scale, like the Kelvin scale, is an absolute temperature scale, meaning its zero point (0 $^\circ R$) corresponds to absolute zero, the theoretical temperature at which all molecular motion ceases. The key difference is that the Rankine scale uses the Fahrenheit degree as its unit interval, whereas the Kelvin scale uses the Celsius degree.

Conversion Formulas

Here's how to convert between Rankine and other common temperature scales:

• Rankine to Fahrenheit:

  $^\circ R = ^\circ F + 459.67$

• Rankine to Celsius:

  $^\circ R = (^ \circ C + 273.15) \times \frac{9}{5}$

• Rankine to Kelvin:

  $^\circ R = K \times \frac{9}{5}$

The zero point of the Rankine scale is absolute zero, which is −459.67 $^\circ F$ or -273.15 $^\circ C$.

Historical Context and William Rankine

William John Macquorn Rankine (1820-1872) was a prominent Scottish engineer and physicist. He made significant contributions to thermodynamics, engine design, and soil mechanics. The Rankine cycle, a fundamental concept in thermodynamics describing the operation of heat engines, is also named after him. While he is known for the Rankine scale, his broader work in thermodynamics had a more lasting impact. He was the first to use the term "Thermodynamics"

Practical Applications and Examples

While not as widely used as Celsius, Fahrenheit, or Kelvin, the Rankine scale finds applications in specific engineering contexts, particularly in the United States, especially when dealing with thermodynamic calculations.

• Thermodynamics: In engineering thermodynamics, the Rankine scale is valuable when absolute temperature values are needed, simplifying calculations involving energy transfer and thermodynamic processes.
• Combustion: When analyzing combustion processes, using absolute temperature scales like Rankine avoids potential issues with negative temperature values in calculations.
• Aviation: Although less common now, some older engineering practices in aviation might have utilized Rankine for certain calculations related to engine performance or atmospheric conditions.

Examples of approximate Rankine values for common temperatures:

• Freezing point of water: 491.67 $^\circ R$
• Boiling point of water: 671.67 $^\circ R$
• Standard room temperature (25 $^\circ C$ or 77 $^\circ F$): 536.67 $^\circ R$

Advantages and Disadvantages

Advantages:

• It is an absolute temperature scale, which is useful in thermodynamic calculations.
• It uses the Fahrenheit degree, which is familiar to engineers in the United States.

Disadvantages:

• It is not as widely used as Celsius, Fahrenheit, or Kelvin.
• The Fahrenheit degree is smaller than the Celsius degree, which can make calculations more difficult.

Further Reading

For a deeper understanding, consider exploring these resources:

• Thermodynamic temperature - Wikipedia

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.