GXMO Radiation Physics and Safety 4

Question 1

What is Bremsstrahlung radiation?

Accepted Answer

X-rays produced when high-speed electrons are slowed and deflected by the atomic nucleus

Answer

Radiation produced by nuclear decay

Answer

Radiation emitted during the photoelectric effect

Answer

Scatter produced in patient tissue

Question 2

A radiographer increases kVp while reducing mAs to maintain similar image density. What effect does this have on patient dose?

Accepted Answer

Patient dose decreases

Answer

Patient dose increases significantly

Answer

Patient dose remains exactly the same

Answer

Patient dose is unaffected because only mAs matters

Question 3

Which of the following is an example of a stochastic radiation effect?

Accepted Answer

Radiation-induced cancer

Answer

Radiation-induced cataracts

Answer

Radiation-induced skin erythema

Answer

Acute radiation syndrome

Question 4

What is the recommended minimum source-to-skin distance (SSD) for stationary x-ray equipment used in general radiography?

Accepted Answer

38 cm (15 inches)

Answer

15 cm (6 inches)

Answer

30 cm (12 inches)

Answer

100 cm (40 inches)

Question 5

What type of radiation survey instrument is best suited for detecting low levels of contamination or locating the edge of a radiation field?

Accepted Answer

Geiger-Müller (GM) detector

Answer

Cutie pie ionization chamber

Answer

Scintillation detector

Answer

Film badge dosimeter

Question 6

Lead aprons used in diagnostic radiology typically provide shielding equivalent to how much lead?

Accepted Answer

0.50 mm Pb

Answer

0.10 mm Pb

Answer

0.25 mm Pb

Answer

1.0 mm Pb

Question 7

What is pair production and at what minimum photon energy does it occur?

Accepted Answer

Creation of an electron-positron pair from a photon near a nucleus; requires at least 1.02 MeV

Answer

Electron ejection from outer shell; occurs above 10 keV

Answer

Complete photon absorption creating an ion pair; occurs above 33 keV

Answer

Coherent scatter of two photons; occurs at any energy