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Roentgen (unit)

The roentgen or röntgen (/ˈrɛntɡən, -dʒən, ˈrʌnt-/; symbol R) is a legacy unit of measurement for the exposure of X-rays and gamma rays, and is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air (statcoulomb per kilogram). In 1928, it was adopted as the first international measurement…

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Named after
Wilhelm Röntgen
SI base units
2.58×10−4 A⋅s/kg
Symbol
R
Unit of
Exposure to ionizing radiation
Unit system
Legacy unit

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Overview

History

Development of replacement radiometric quantities

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Roentgen (unit)

Nodes55
Edges54
Triples5
Avg. degree1.96
Density0.036364
Components1

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Roentgen (unit)

Top relations

Named after · 1
Roentgen (unit) → Wilhelm Röntgen
SI base units · 1
Roentgen (unit) → 2.58×10−4 A⋅s/kg
Symbol · 1
Roentgen (unit) → R
Unit of · 1
Roentgen (unit) → Exposure to ionizing radiation
Unit system · 1
Roentgen (unit) → Legacy unit

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Important terminology

roentgen radiation unit units rad air dose absorbed defined gray kg exposure used international definition si per quantity nist one

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Roentgen (unit)Named afterWilhelm Röntgen1.00infobox
Roentgen (unit)SI base units2.58×10−4 A⋅s/kg1.00infobox
Roentgen (unit)SymbolR1.00infobox
Roentgen (unit)Unit ofExposure to ionizing radiation1.00infobox
Roentgen (unit)Unit systemLegacy unit1.00infobox

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