Convert Square Rod (rod²) to Barn (b (area)) instantly.
About these units
Square Rod (rod²)
A square rod, also known as a perch or pole in some traditions, equals the area of a square one rod on each side (1 rod = 16.5 feet). This results in 272.25 square feet. Square rods were widely used in medieval English farming and early American surveying to measure garden plots, small fields, and building sites. Because land taxes were often assessed per rod, the unit became a practical economic tool as well. Though no longer widely used, the square rod appears in historical deeds and archival surveys, making it critical for land historians and legal property research.
Barn (b (area))
The barn is an area unit used almost exclusively in nuclear and particle physics, equal to 10⁻²⁸ square meters. Despite its incredibly tiny size, the barn emerged from humorous origins: early nuclear physicists joked that certain atomic nuclei were "as big as a barn" compared to the particles trying to hit them. The barn quantifies interaction cross-sections—essentially probabilities of particles colliding or interacting with nuclei. Because fundamental forces operate at extremely small scales, typical cross-section values lie in the microbarn, nanobarn, or picobarn range. The barn is essential for describing reaction rates in particle accelerators, nuclear reactors, and astrophysical processes such as stellar fusion.