1) A material is found to have a tenth-thickness of 2.3 cm for 1.25-MeV gamma rays, (a) What is the linear attenuation coefficient for this material? (b) What is the half-thickness? (c) What is the mean-free-path length for 1.25-MeV photons in this material?
2;The specific rate of energy loss (-dE/ρdx) of a 5 MeV
-12proton in silicon is 59 keV mg cm and its range R' is 50 mg
-2cm . Calculate values of (-dE/ρdx) and range R' for deuterons,
tritons, 3He and a particles, all of which have the same speed as the proton.
18 23;A pulse of 10100 keV X-ray photons per m is directed at
right angles on to a 5 mm thick slab of iron. Calculate the
-3temperature increase of the slab. Density of iron = 7870kg m
mass attenuation coefficient for l00 keV photons on iron = 0.04 2-1-1-1m kg; specific heat capacity of iron = 106 J kgK .
4) During a diagnostic X-ray, a broken leg with a mass of 5 kg receives an equivalent dose of 0.5 mSv. If the X-ray energy is 50 keV, how many X-ray photons were absorbed?
5) If a radionuclide, with a physical half-life t, is ingested and 1/2
behas a biological half-life t. What is the effective half-life t, 1/21/2
for the removal of the radioactive nuclide from the system?
6) What is the gamma-ray absorbed dose rate (Gy/h) in an infinite air medium at a distance of 10 cm from a 1 mCi point
13source of N? Decay data and energies can be found at this site: http://www.nndc.bnl.gov/mird/