What is Temperature
The degree of hotness or coldness of the body is called the temperature of the body.
A candle flame is hot and is said to be at high temperatures, whilst ice cream is cold and is said to be at reduced/low temperatures.
Scales of temperature
A scale is indicated around the thermometer. The warmth of the body in touch with the thermometer can be read on that scale. Three scales of temperatures are in common usage. These are:
- Celsius scale or centigrade scale
- Fahrenheit scale
- Kelvin scale
Celsius scale or centigrade scale
Celsius, or centigrade, is a unit and scale of measurement for temperature. It is one of the most widely used temperature units all over the world. This scale is called after the Swedish astronomer Anders Celsius (1701-1744), who produced a comparable temperature scale. The degree of measurement is Celsius (°C).
On the Celsius scale, the interval between upper and lower stationary points is divided into 100 equal parts. The lower fixed point is indicated as 0 °C that is the freezing point of water and the higher point is indicated as 100 °C the boiling point of water.
Fahrenheit scale
It is established on a scale suggested in 1724 by physicist Daniel Gabriel Fahrenheit (1686-1736). The degree of measurement is Fahrenheit (°F). On this scale, the interval between the upper and lower points is divided into 180 equal components. Its lower fixed point is indicated as 32 °F and the upper stationary point is indicated as 212 °F.
With this scale, the water freezing point is defined as 32 °F, whilst the water boiling point is defined as 212 °F.
Kelvin scale
A Kelvin is a unit of measurement for temperature. It is called after the Glasgow University engineer and physicist William Thomson, 1st Baron Kelvin. In SI units, the unit of temperature is Kelvin (K) and its scale is also named Kelvin scale of temperature. The interval between the upper and lower factors is split into 100 equal parts. Therefore, an alteration in 1°C is equivalent to a change of 1K. The lower fixed point with this scale equates to 273 K and the upper fixed point is at 373 K.
Absolute Zero
The zero on the Kelvin (K) scale is known as the absolute zero and is equivalent to – 273 °C. Absolute zero is the possible coldest temperature. Absolute zero describes a condition where all of the energy of some system is extracted. It is the ideal temperature where gases can become liquified. But this temperature is impossible to reach.
Conversion Of temperature into different scales
From Celsius to Kelvin
This can be obtained by using this formula.
Example:
What will be the temperature in Kelvin when it is 30 °C on the Celsius scale?
C = 30°
By putting the value of C
From Kelvin to Celsius
This can be obtained by subtracting 273 from the given temperature.
Example:
Change 300K on Kelvin scale into Celsius scale
C = 27°
From Celsius to Fahrenheit
Example:
Convert 50°C to Fahrenheit scale
From Fahrenheit to Celsius
Convert 100 °F into Celsius
MCQs
- What is the definition of temperature?
- A) The degree of brightness of an object
- B) The degree of hotness or coldness of a body
- C) The amount of energy stored in an object
- D) The speed of molecules in an object
- Answer: B) The degree of hotness or coldness of a body
- Who is the Swedish astronomer after whom the Celsius scale is named?
- A) Daniel Gabriel Fahrenheit
- B) William Thomson
- C) Anders Celsius
- D) Lord Kelvin
- Answer: C) Anders Celsius
- Which temperature scale is based on a scale suggested by physicist Daniel Gabriel Fahrenheit?
- A) Kelvin scale
- B) Celsius scale
- C) Fahrenheit scale
- D) Centigrade scale
- Answer: C) Fahrenheit scale
- What is the freezing point of water on the Fahrenheit scale?
- A) 0 °F
- B) 32 °F
- C) 100 °F
- D) 212 °F
- Answer: B) 32 °F
- Who is the physicist after whom the Kelvin scale is named?
- A) Anders Celsius
- B) Daniel Gabriel Fahrenheit
- C) William Thomson
- D) Lord Kelvin
- Answer: C) William Thomson
- What is the lower fixed point on the Kelvin scale?
- A) 0 K
- B) 32 K
- C) 100 K
- D) 273 K
- Answer: A) 0 K
- What temperature scale is widely used as the standard in scientific measurements?
- A) Fahrenheit scale
- B) Kelvin scale
- C) Celsius scale
- D) Centigrade scale
- Answer: B) Kelvin scale
- What temperature scale is named after a Scottish physicist and engineer?
- A) Celsius scale
- B) Fahrenheit scale
- C) Kelvin scale
- D) Centigrade scale
- Answer: C) Kelvin scale
- What is the interval between the upper and lower points on the Fahrenheit scale divided into?
- A) 90 equal parts
- B) 100 equal parts
- C) 180 equal parts
- D) 360 equal parts
- Answer: C) 180 equal parts
- What is the boiling point of water on the Celsius scale?
- A) 0 °C
- B) 32 °C
- C) 100 °C
- D) 212 °C
- Answer: C) 100 °C
- Which temperature scale uses the freezing point of water as its lower fixed point?
- A) Kelvin scale
- B) Fahrenheit scale
- C) Celsius scale
- D) Centigrade scale
- Answer: C) Celsius scale
- What is the equivalent of 0 °C on the Kelvin scale?
- A) 0 K
- B) 32 K
- C) 100 K
- D) 273 K
- Answer: D) 273 K
- What does absolute zero represent?
- A) The maximum temperature achievable
- B) The temperature at which all motion ceases
- C) The temperature at which water boils
- D) The temperature at which gases become liquids
- Answer: B) The temperature at which all motion ceases
- Who proposed a scale of temperature based on the freezing and boiling points of water?
- A) Lord Kelvin
- B) Daniel Gabriel Fahrenheit
- C) Anders Celsius
- D) William Thomson
- Answer: C) Anders Celsius
- What is the absolute zero temperature in Celsius?
- A) 0 °C
- B) -273 °C
- C) 100 °C
- D) -100 °C
- Answer: B) -273 °C
- Which temperature scale is primarily used in the United States?
- A) Celsius scale
- B) Kelvin scale
- C) Fahrenheit scale
- D) Centigrade scale
- Answer: C) Fahrenheit scale
- What is the difference in temperature between the freezing and boiling points of water on the Celsius scale?
- A) 32 °C
- B) 100 °C
- C) 180 °C
- D) 212 °C
- Answer: B) 100 °C
- What is the interval between the upper and lower points on the Kelvin scale?
- A) 90 equal parts
- B) 100 equal parts
- C) 180 equal parts
- D) 273 equal parts
- Answer: D) 273 equal parts
Wrap up
Temperature Scales and Conversion
In this tutorial, we delve into the concept of temperature scales and the methods for converting temperatures from one scale to another. Temperature, as defined, reflects the degree of hotness or coldness of a body. It serves as a fundamental parameter in various fields, ranging from everyday life to scientific research.
Understanding Temperature Scales
Temperature measurement relies on several scales, each with its own unique characteristics and applications. The three primary temperature scales in common usage are the Celsius (or centigrade), Fahrenheit, and Kelvin scales.
Celsius Scale
Named after Swedish astronomer Anders Celsius, the Celsius scale is widely adopted globally. It designates 0°C as the freezing point and 100°C as the boiling point of water, providing a convenient and intuitive reference for temperature measurement.
Fahrenheit Scale
The Fahrenheit scale, proposed by physicist Daniel Gabriel Fahrenheit, is commonly used in the United States and a few other countries. It sets the freezing point of water at 32°F and the boiling point at 212°F. Despite its limited global adoption, it remains relevant in certain contexts.
Kelvin Scale
The Kelvin scale, named after physicist William Thomson, also known as Lord Kelvin, is based on absolute zero as its zero point. This scale is fundamental in scientific applications, particularly in thermodynamics and physics. Each increment of temperature on the Kelvin scale corresponds to an equivalent increment on the Celsius scale.
Temperature Conversion
Converting temperatures between different scales is a crucial skill in various fields, facilitating communication and data analysis. Understanding the conversion formulas and relationships between scales enhances proficiency in temperature-related tasks.
Celsius to Fahrenheit and Kelvin
Converting temperatures from Celsius to Fahrenheit and Kelvin, and vice versa, involves applying specific conversion formulas. These formulas enable seamless transition between different temperature scales, providing flexibility and precision in temperature measurement and analysis.
Absolute Zero
Absolute zero, denoted as 0 Kelvin (-273.15°C), represents the lowest possible temperature theoretically attainable. At this temperature, molecular motion ceases entirely, rendering any further decrease in temperature impossible. While absolute zero is unattainable in practice, its conceptual significance underscores the foundations of thermodynamics and the behavior of matter at extreme conditions.
Conclusion
In conclusion, temperature scales and conversion play pivotal roles in various disciplines, ranging from everyday applications to advanced scientific research. By comprehensively understanding the characteristics of different temperature scales and mastering temperature conversion techniques, individuals can effectively interpret temperature data and contribute to advancements in numerous fields.