Nuclear physics Radioactive isotopes are often introduced into the body through the bloodstream. Their spread through…

Nuclear physics Radioactive isotopes are often introduced into the body through the bloodstream. Their spread through the body can then be monitored by detecting the appearance of radiation in different organs. 1311, a B- emitter with a half-life of 8.0 days is one such tracer. Suppose a scientist introduces a sample with an activity of 375 Bq and watches it spread to the organs. Assuming that the sample all went to the thyroid gland, what will be the decay rate (activity) in that gland 24 days later? If the subject’s thyroid has a mass of 20 grams, and each B- is of energy 5 keV, what is the total dose of radiation the thyroid receives?