Barn to Square Kilometer Converter
Unit Converter
Instant · Precise · Universal
23 units available
6 categories total
How to Convert Barn to Square Kilometer
To convert barns to m²: multiply by 10⁻²⁸. To fm²: multiply by 100.
1 b = 10⁻²⁸ m² = 100 fm². Millibarns (mb), microbarns (µb), and nanobarns (nb) are common submultiples.
For example, 1 Barn (b) = 1.000000e-34 Square Kilometer (km²).
Barn to Square Kilometer — Common Values
| Barn (b) | Square Kilometer (km²) |
|---|---|
| 0.1 | 1.000000e-35 |
| 0.5 | 5.000000e-35 |
| 1 | 1.000000e-34 |
| 2 | 2.000000e-34 |
| 5 | 5.000000e-34 |
| 10 | 1.000000e-33 |
| 25 | 2.500000e-33 |
| 50 | 5.000000e-33 |
| 100 | 1.000000e-32 |
| 500 | 5.000000e-32 |
| 1000 | 1.000000e-31 |
About Barn (b)
Definition
The barn is a unit of area equal to 10⁻²⁸ m², used to express nuclear cross-sections — the effective target area of subatomic particles.
Mathematical Relationship
1 b = 10⁻²⁸ m² = 100 fm². Millibarns (mb), microbarns (µb), and nanobarns (nb) are common submultiples.
Conversion Formula
To convert barns to m²: multiply by 10⁻²⁸. To fm²: multiply by 100.
Practical Applications
Quantifying nuclear reaction probabilities, neutron absorption, and particle scattering in reactor design.
Interesting Facts
The physicists named it 'barn' as a joke: nuclei were 'as big as a barn' compared to what they expected. Later units include 'outhouse' (10⁻⁶ barns) and 'shed' (10⁻²⁴ barns).
Common Mistakes
Thinking a barn is a large area — at the human scale 10⁻²⁸ m² is incomprehensibly small.
Educational Tips
Cross-section = probability of interaction. A bigger barn value means a particle is more likely to 'hit the target' — hence the barn analogy.
About Square Kilometer (km²)
Definition
The square kilometer is a metric unit of area equal to 1,000,000 square meters, or a square with sides of 1 kilometer.
Mathematical Relationship
1 km² = 1,000,000 m² = 100 ha = 247.105 acres ≈ 0.3861 mi².
Conversion Formula
To convert km² to mi²: multiply by 0.3861. To hectares: multiply by 100. To acres: multiply by 247.105.
Practical Applications
Country areas, national park sizes, city footprints, forest coverage, and watershed boundaries.
Interesting Facts
Vatican City = 0.44 km². Manhattan = 59.1 km². Russia = 17,098,242 km² (largest country). Earth's surface = 510,072,000 km².
Common Mistakes
Thinking 1 km² = 1,000 m² (it's actually 1,000,000 m²). Area scales as the square of the linear dimension.
Educational Tips
1 km = 1,000 m, but 1 km² = 1,000² m² = 1,000,000 m². Always square the conversion factor for area.