Question
The 'rad' is the correct unit used to report the measurement of
A.
the ability of a beam of gamma ray photons to produce ions in a target
B.
the energy delivered by radiation to a target
C.
the biological effect of radiation
D.
the rate of decay of a radioactive source
Answer :
the biological effect of radiation
Solution :
The risk posed to a human being by any radiation exposure depends partly upon the absorbed dose, the amount of energy absorbed per gram of tissue. Absorbed dose is expressed in rad. A rad is equal to 100 ergs of energy absorbed by 1 gram of tissue. The more modern, internationally adopted unit is the gray (named after the English medical physicist L. H. Gray); one gray equals 100 rad.