# Radiation Therapy Physics- Mosby Board Review Questions

 The half life of Ir 192 is 74 days. The decay constant is: In2/74= 0.00094 days-1 What are the differences between an electron and a proton? Electrons are light, negatively charged particles:they can collide and interact with other particlesProtons are are heavy, positively charged particles that can only interact with electrons Types of decay include all of the following EXCEPT: 1)alpha 2) neutron 3)beta 4)internal conversion neutron During x-ray production, the reslting x-ray bem comes from electrons colliding with the target and causing interactions such as: 1)characteristic radiation 2)bremstrahlung radiation 3)auger electrons 4) all of the above all of the above The positive side of the x-ray tube is known as the: anode  "A's are positive :) " A radioactive source has an initial activity of 60 mCi. It's half life is 8 days. What is the remaining activity after 10 days? 25 mCiA=Ao(.5)t/hA=60(.5)10/8 The average life of a source with a half life of 8 days is: 8 (1.44)=11.5 daysT1/2(1.44) The ratio of x-ray to heat in x-ray production is: Variable  depending on the maximum energy of the electrons traversing the tube The radioactive decay of a isotope is characterized by its: decay constant An elastic collision is one in which: the incoming electron gives up all of its energy to the electron it encounters The energy of an electromagnetic radiation is inversely proportional to its wavelength If a 50 keV electron collides with an inner shell electron with a binding energy of 25 keV, the resulting photoelectron will have an energy of: 25 keV(50-25) The energy of an electromagnetic radiation is directly proportional to its: frequency List photon interactions:(5) comptoncoherentphotodisintegrationphotoelectricpair production List electron interactions(2): bremmstrahlungcharacteristic The decay of Cobalt-60 to stable lead is an example of ____decay. beta negative (gamma rays and beta negative) Regarding isotopes, isotopes of an element have the same number of______but a different number of neutrons. protons Match the following: Isotopes: ___        A. Ir192   Ir192m Isobars:  ___         B.  27Fe59  27Fe58 Isotones: ___        C. 28Ni60  31Ga60 Isomers: ____        D.  11Na22   10Ne27 Isotopes: _B__   (7Fe59  27Fe58)     Isobars:  _C__     ( 28Ni60  31Ga60 )  Isotones: _D__     (1Na22   10Ne27)Isomers: _A___    (Ir192   Ir192m) Ir192  is an ________. isomer If the decay constant of a particularisotope is 45 sec-1, the half life is: 0.015 secIn2/decay constant = half-life If the half-life of Co-60 is 5.26 years, what is the average life? 1.44(5.26)=7.57 years Authorjaxkaty5437 ID262446 Card SetRadiation Therapy Physics- Mosby Board Review Questions DescriptionRadiation Therapy Physics- Mosby Board Review Questions Updated2014-03-08T14:41:13Z Show Answers