Units to measure Radioactivity?
VerifiedAnswer: Curie and Becquerel
Explanation:
Radioactivity is the spontaneous decay of unstable atomic nuclei, releasing energy in the form of radiation. To measure this phenomenon accurately, scientists use specific units that help us understand the rate at which radioactive decay occurs. The two primary units for measuring radioactivity are Curie (Ci) and Becquerel (Bq).
The Becquerel is the modern SI (International System of Units) unit for measuring radioactivity. Named after French physicist Henri Becquerel, who discovered radioactivity, one Becquerel represents one nuclear decay per second. This means if you have a radioactive sample with an activity of 1 Bq, exactly one atom in that sample decays every second. The Becquerel provides a straightforward way to express radioactive decay rates, making it easy to work with in scientific calculations.
The Curie is an older unit that was widely used before the SI system became standard. Named after Marie and Pierre Curie, the pioneers of radioactivity research, one Curie equals approximately 3.7 × 10¹⁰ Becquerels. This large number comes from the fact that the Curie was originally defined based on the activity of one gram of radium-226. While the Curie is still used in some applications, particularly in medicine and industry, the Becquerel is now the preferred scientific standard.
Both units measure the same physical quantity - the number of radioactive decays occurring per unit time. However, they differ significantly in magnitude. For practical purposes, common multiples and submultiples are used:
• Kilobecquerel (kBq) = 1,000 Bq • Megabecquerel (MBq) = 1,000,000 Bq • Gigabecquerel (GBq) = 1,000,000,000 Bq • Millicurie (mCi) = 0.001 Ci • Microcurie (μCi) = 0.000001 Ci
Understanding these units is crucial for various applications. In nuclear medicine, doctors use these measurements to determine appropriate doses of radioactive tracers for diagnostic imaging. In nuclear power plants, engineers monitor radioactivity levels to ensure safe operation. Environmental scientists use these units to assess contamination levels and track the movement of radioactive materials in ecosystems.
It's important to note that these units measure activity (the rate of decay) rather than the total amount of radiation exposure or dose. For measuring radiation dose, different units like Gray (Gy) and Sievert (Sv) are used. The Curie and Becquerel specifically quantify how "active" a radioactive source is, telling us how frequently atoms are undergoing radioactive decay at any given moment.
