Simulacro ACOFIMED Temas 1 y 2

Select all true statements regarding internal conversion.

• Internal always involves emission of a gamma ray

• Internal conversion is most likely in radionuclides with a high neutron-to-proton ratio

• Internal conversion allows an excited nuclear state to de-excite without changing atomic constituents

• Internal conversion may result in the emission of characteristic x-rays

Select all true statements about photoelectric interactions.

• Interaction probability is inversely proportional to E^3

• Photoelectric interaction is more likely in outer orbital electrons

• Interaction probability is proportional to E^2

• Photoelectric interactions are more likely in lead than in tungsten

Select all likely decay methods of a radionuclide with a low neutron-to-proton ratio.

• Fusion

• Beta- Decay

• Electron Capture

• Beta+ Decay

A photon beam with an initial fluence of 1000 photons/cm2 is incident on a water phantom. The beam is comprised of equal parts 50keV and 100keV photons. The mass attenuation coefficient of 50keV photons in water is 0.23 (cm2/g) amd the mass attenuation coefficient of 100keV photons in water is 0.17 (cm2/g). Find the fluence transmitted through 5cm of water.

• • 368 photons/cm²

• • 341 photons/cm²

• • 322 photons/cm²

• 372 photons/cm²

1 mole of pure Uranium-238 (half life = 4.468 billion years) is allowed to decay for 10 years. How much Radium-226 (half life = 1600 years) is present in the sample at the end of this time?

• • 2.78 micrograms

• 0.35 micrograms

• • 0.08 micrograms

• • 13 micrograms

What is the minimum kinetic energy per beta particle in triplet production?

• 0 MeV

• • 0.255 MeV

• • 0.511 MeV

• 0.341 MeV

Stopping power is proportional to:

• • v²/z

• • zv

• z²/v²

• • z/v²

How many Bq per Ci?

• • 2.99 x 10⁸

• • 6.02 x 10¹⁰

• 37 x 10⁹

• • 3.7 x 10⁶

You are given an unknown shielding material. You find that it has a density of 11.4g/cc and a TVL of 5.7cm for your 6MV photon field. What is the mass attenuation coefficient of this material?

• • 0.17 cm²/g

• • 0.02 cm²/g

• 0.04 cm²/g

• • 0.40 cm²/g

1Gy is equal to how many erg/g?

• 10

• 10,000

• 100

• 1,000