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Convert Rood to Barn (ro to b) instantly with accurate, readable results.
Convert between square meters, acres, square feet, hectares, and other common units with our Area Unit Converter. This intuitive unit conversion tool helps you calculate land size, floor space, and surface area across both metric and imperial systems. Whether you're working on real estate, construction, or geography tasks, our area unit conversion calculator ensures precise and instant results.
Rood (rood) - traditional land area
Rood is a historical Imperial/US customary unit of area equal to one quarter of an acre. Used in older land records, field measurements, and some property descriptions.
- Symbol: none standardized (written as “rood”)
- System: Imperial/US customary (historic)
- Exact relations: 1 rood = 1/4 acre = 40 square rods (perches) = 2.5 square chains
- Other relations: 1 rood = 1 furlong × 1 rod = 10,890 ft² = 1,210 yd²
- Metric equivalents (exact): 1 rood = 1011.7141056 m²
- Typical examples: historical parcel sizes in deeds; subdivision remnants expressed as roods and perches
Barn (b) - nuclear/particle cross-section area
Barn is a non-SI unit of area used in nuclear and particle physics to express interaction cross-sections. The name originated humorously during the Manhattan Project (“as big as a barn”).
- Symbol: b
- System: Non-SI (accepted in high-energy/nuclear physics)
- Exact relations: 1 b = 10⁻²⁸ m² = 10⁻²⁴ cm² = 100 fm²
- Common submultiples: 1 mb = 10⁻³ b; 1 µb = 10⁻⁶ b; 1 nb = 10⁻⁹ b; 1 pb = 10⁻¹² b; 1 fb = 10⁻¹⁵ b; 1 ab = 10⁻¹⁸ b
- Related usage: integrated luminosity often quoted in inverse barns (e.g., fb⁻¹)
- Typical examples: neutron capture and scattering cross-sections; collider process cross-sections reported from barns down to picobarns and femtobarns