Langley (Ly)
One thermochemical calorie per square centimeter: exactly 41,840 J/m². Used in older solar radiation data.
What is a langley?
- Symbol
- Ly
- Quantity
- Heat Density
- Unit system
- other
- Definition
- One thermochemical calorie per square centimeter: exactly 41,840 J/m². Used in older solar radiation data.
- Exact
- Yes, the value is exact by definition
- Source
- NIST Special Publication 811 (2008), Appendix B.8
Common applications
Found in older meteorology and solar radiation records, often as langleys per day.
Langley in other heat density units
- 1 Ly = 41840 J/m²Joule per square meter
- 1 Ly = 41.84 kJ/m²Kilojoule per square meter
- 1 Ly = 0.04184 MJ/m²Megajoule per square meter
- 1 Ly ≈ 0.01162222222 kWh/m²Kilowatt-hour per square meter
- 1 Ly ≈ 3.684225043 BTU/ft²BTU per square foot
Langley quick reference
| Langley | Kilojoule per square meter | BTU per square foot | Joule per square meter |
|---|---|---|---|
| 1 Ly | = 41.84 kJ/m² | ≈ 3.684225043 BTU/ft² | = 41840 J/m² |
| 10 Ly | = 418.4 kJ/m² | ≈ 36.84225043 BTU/ft² | = 418400 J/m² |
| 100 Ly | = 4184 kJ/m² | ≈ 368.4225043 BTU/ft² | = 4184000 J/m² |
| 1000 Ly | = 41840 kJ/m² | ≈ 3684.225043 BTU/ft² | = 41840000 J/m² |
Where the langley fits
The next smaller heat density unit is the BTU per square foot (BTU/ft²). 1 Ly ≈ 3.684225043 BTU/ft², and 1 BTU/ft² ≈ 0.271427502 Ly.
The next larger heat density unit is the megajoule per square meter (MJ/m²). 1 Ly = 0.04184 MJ/m², and 1 MJ/m² ≈ 23.90057361 Ly.
Frequently asked questions
- How many kilojoules per square meter are in one langley?
- One langley = 41.84 kJ/m² (kilojoules per square meter).
- How many BTUs per square foot are in one langley?
- One langley ≈ 3.684225043 BTU/ft² (BTUs per square foot).
- How many joules per square meter are in one langley?
- One langley = 41840 J/m² (joules per square meter).