Radiation Exposure / R → C/kg
Convert Roentgens to Coulombs per kilogram
Convert photon exposure in air using charge per mass. Convert Roentgens (R) to Coulombs per kilogram (C/kg). Find the formula, worked examples, unit definitions, and practical guidance below.
Reverse: Coulombs per kilogram to Roentgens →
How to convert roentgens to coulombs per kilogram
Exposure in C/kg describes ionization in air. It is not absorbed dose in tissue or equivalent dose in sieverts. Those relationships require radiation and material information.
Use x for the value in R, b for the intermediate value in C/kg, and y for the result in C/kg.
C/kg = R × 0.000258
Worked examples
10 R ≈ 0.00258 C/kg
Step 1: (10 × 0.000258) ≈ 0.00258 C/kg.
Step 2: 0.00258 ÷ 1 ≈ 0.00258 C/kg.20 R ≈ 0.00516 C/kg
Step 1: (20 × 0.000258) ≈ 0.00516 C/kg.
Step 2: 0.00516 ÷ 1 ≈ 0.00516 C/kg.
Results are rounded to 12 significant digits. Converting units does not increase the precision of the original measurement. Very large or small values outside JavaScript’s finite numeric range are rejected.
About Roentgens
Roentgens (R) measures radiation exposure under the conventions above. The base value in C/kg is (x × 0.000258), where x is the numerical value in R. Factors shown here are rounded for display; calculations use the stored factor.
About Coulombs per kilogram
Coulombs per kilogram (C/kg) measures radiation exposure under the conventions above. The base value in C/kg is (x × 1), where x is the numerical value in C/kg. Factors shown here are rounded for display; calculations use the stored factor.
Definitions and sources
Carry the same physical assumptions into subsequent physics calculations.
Roentgens to coulombs per kilogram reference table
| Roentgens (R) | Coulombs per kilogram (C/kg) |
|---|---|
| 1 | 0.000258 |
| 5 | 0.00129 |
| 10 | 0.00258 |
| 25 | 0.00645 |
| 50 | 0.0129 |
| 100 | 0.0258 |
| 1000 | 0.258 |
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