Convert Curies to Becquerels
Convert Curies (Ci) to Becquerels (Bq) instantly and accurately.
Conversion Formula
Bq = Ci × 37000000000
About Curies
The curie (Ci) equals exactly 3.7 × 10¹⁰ Bq = 37 GBq, originally defined as the activity of 1 g of ²²⁶Ra. Still widely used in the US: ⁶⁰Co teletherapy sources are 5000-15000 Ci; ¹³⁷Cs blood irradiators are 1000-40000 Ci; NRC source licences for industrial radiography cite Ci limits. 1 Ci = 3.7 × 10¹⁰ Bq.
About Becquerels
The becquerel (Bq) is the SI coherent unit of radioactivity, defined as exactly one nuclear disintegration per second. Named after Henri Becquerel (discoverer of radioactivity, 1896), it replaced the curie in SI. Household smoke detector ²⁴¹Am sources contain ~30 kBq; a banana contains ~15 Bq of ⁴⁰K. 1 Bq = 1 s⁻¹.
Quick Reference Table
| Curies (Ci) | Becquerels (Bq) |
|---|---|
| 1 Ci | 3.7 × 1010 Bq |
| 2 Ci | 7.4 × 1010 Bq |
| 5 Ci | 1.85 × 1011 Bq |
| 10 Ci | 3.7 × 1011 Bq |
| 25 Ci | 9.25 × 1011 Bq |
| 50 Ci | 1.85 × 1012 Bq |
| 100 Ci | 3.7 × 1012 Bq |