A 2.0-kg tumor is being irradiated by a radioactive source. The tumor receives an absorbed dose of

Question:

A 2.0-kg tumor is being irradiated by a radioactive source. The tumor receives an absorbed dose of 12 Gy in a time of 850 s. Each disintegration of the radioactive source produces a particle that enters the tumor and delivers an energy of 0.40 MeV. What is the activity DN/Dt (see Section 31.6) of the radioactive source?