Question

A 60Co source with activity 15.0 Ci is imbedded in a tumor that has a mass...

A 60Co source with activity 15.0 Ci is imbedded in a tumor that has a mass of 0.520 kg . The Co source emits gamma-ray photons with average energy of 1.15 MeV . Half the photons are absorbed in the tumor, and half escape.
(A) What energy is delivered to the tumor per second?

(B) What absorbed dose (in rad) is delivered per second?

(C) What equivalent dose (in rem) is delivered per second if the RBE for these gamma rays is 0.700?

(D) What exposure time is required for an equivalent dose of 200 rem ?

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