Absolute temperature and the kelvin scale | Physical Processes | MCAT | Khan Academy
khanacademymedicine・1 minute read
Temperature is a measure of particle kinetic energy, with Kelvin, Celsius, and Fahrenheit being common scales. Kelvin is favored for its positive value range, reaching absolute zero at -273.15 degrees Celsius.
Insights
- Temperature is a measure of particle movement, with faster particles indicating higher temperatures.
- Kelvin is favored as the SI unit for temperature due to its positive values and absolute zero at 0 Kelvin, representing the coldest possible temperature.
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Recent questions
What is temperature?
Temperature is a measure of particle kinetic energy.
What are the three common temperature scales?
Kelvin, Celsius, and Fahrenheit are common temperature scales.
How do you convert Celsius to Kelvin?
Convert Celsius to Kelvin by adding 273.15 units.
What is absolute zero?
Absolute zero is the absence of particle kinetic energy.
Why is Kelvin often used as the standard SI unit for temperature?
Kelvin is preferred due to its positive value range and absolute zero.
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Summary
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Temperature Scales: Kelvin, Celsius, Fahrenheit, Conversions, Absolute Zero
- Temperature is a measure of the average kinetic energy of particles in a system, with faster-moving particles indicating higher kinetic energy and thus a greater temperature.
- The three most commonly used temperature scales are Kelvin, Celsius, and Fahrenheit, with the freezing point of water at 0 degrees Celsius and 273.15 Kelvin, and the boiling point at 100 degrees Celsius and 373.15 Kelvin.
- Converting between Celsius and Kelvin involves adding or subtracting 273.15 units, while converting between Fahrenheit and Celsius requires a ratio of 9 to 5 and adjusting for the different zero points.
- Both Celsius and Fahrenheit scales can have negative values, as seen with -40 degrees Celsius being equivalent to -40 degrees Fahrenheit, while the Kelvin scale only has positive values, with absolute zero at 0 Kelvin.
- Absolute zero, at 0 Kelvin, represents the absence of any kinetic energy in particles, as dictated by the laws of physics, making it the coldest possible temperature.
- The Kelvin scale is often used as the standard SI unit for temperature due to its positive value range, with absolute zero occurring at -273.15 degrees Celsius.




