Convert joule/centigram [J/cg] to rad [rd] Online | Free radiation-absorbed-dose Converter

Joule per Centigram [J/cg]: A Unit of Energy per Mass

The joule per centigram (J/cg) expresses the amount of energy absorbed or delivered per unit mass, specifically joules of energy per centigram (1 centigram = 0.01 grams). This unit represents energy density on a small mass scale.

To relate it to standard radiation dose units: since 1 gray (Gy) equals 1 joule per kilogram (J/kg), and 1 centigram equals 10⁻⁵ kilograms, then

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  1 J/cg = 1 joule per 0.00001 kg = 100,000 J/kg = 100,000 Gy.

  
  

This means that 1 J/cg corresponds to a very high absorbed radiation dose, much greater than typical doses used in medicine or radiation safety.

J/cg could be useful in very specialized fields where energy deposition is considered over tiny masses, such as microdosimetry, materials science, or radiation effects at microscopic scales.

In general, joule per centigram is a high-precision measure for energy density per small mass, but it’s not commonly used in everyday radiation measurement, where grays or their subunits are preferred.

Rad [rd]: A Legacy Unit of Absorbed Radiation Dose

The rad (short for radiation absorbed dose) is a legacy unit used to measure the amount of ionizing radiation energy absorbed per unit mass of material. It was widely used before the adoption of the gray (Gy) in the International System of Units (SI).

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  1 rad = 0.01 gray (Gy)

  
  
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  This means that 1 rad corresponds to the absorption of 0.01 joules of radiation energy per kilogram of matter.

  
  

The rad was commonly used in medical, industrial, and scientific settings to quantify radiation doses. Although now largely replaced by the gray for consistency and international standardization, the rad is still sometimes referenced in older research, medical records, and certain fields.

The rad and its subunits (like the millirad) helped establish the groundwork for understanding radiation exposure and effects before the transition to the more precise and universally accepted gray unit.