Per kelvin (1/K)
SI unit of the coefficient of thermal expansion: relative change in size per kelvin of temperature change.
What is a reciprocal kelvin?
- Symbol
- 1/K
- Quantity
- Thermal Expansion
- Unit system
- SI
- Definition
- SI unit of the coefficient of thermal expansion: relative change in size per kelvin of temperature change.
- Exact
- Yes, the value is exact by definition
- Source
- SI Brochure, 9th edition (BIPM, 2019)
Common applications
Used in physics and materials data for expansion coefficients, often written with a power of ten, such as 1.2 × 10⁻⁵ K⁻¹ for steel.
Per kelvin in other thermal expansion units
- 1 1/K = 1 1/°CPer degree Celsius
- 1 1/K ≈ 0.5555555556 1/°FPer degree Fahrenheit
- 1 1/K = 1000000 ppm/KPart per million per kelvin
- 1 1/K ≈ 555555.5556 ppm/°FPart per million per degree Fahrenheit
Per kelvin quick reference
| Per kelvin | Part per million per kelvin | Part per million per degree Fahrenheit | Per degree Celsius |
|---|---|---|---|
| 1 1/K | = 1000000 ppm/K | ≈ 555555.5556 ppm/°F | = 1 1/°C |
| 10 1/K | = 10000000 ppm/K | ≈ 5555555.556 ppm/°F | = 10 1/°C |
| 100 1/K | = 100000000 ppm/K | ≈ 55555555.56 ppm/°F | = 100 1/°C |
| 1000 1/K | = 1000000000 ppm/K | ≈ 555555555.6 ppm/°F | = 1000 1/°C |
Where the reciprocal kelvin fits
The next smaller thermal expansion unit is the part per million per degree Fahrenheit (ppm/°F). 1 1/K ≈ 555555.5556 ppm/°F, and 1 ppm/°F = 0.0000018 1/K.
The next larger thermal expansion unit is the reciprocal degree Fahrenheit (1/°F). 1 1/K ≈ 0.5555555556 1/°F, and 1 1/°F = 1.8 1/K.
Frequently asked questions
- How many parts per million per kelvin are in one reciprocal kelvin?
- One reciprocal kelvin = 1000000 ppm/K (parts per million per kelvin).
- How many parts per million per degree Fahrenheit are in one reciprocal kelvin?
- One reciprocal kelvin ≈ 555555.5556 ppm/°F (parts per million per degree Fahrenheit).
- How many reciprocal degrees Celsius are in one reciprocal kelvin?
- One reciprocal kelvin = 1 1/°C (reciprocal degrees Celsius).