Radiographic Science

1.

1 point

The probability of photoelectric absorption occurring is greatest when:

The energy of the incoming photon just equals the ionisation energy of the atom it is interacting with

The energy of the incoming photon is less than the ionisation energy of the atom it is interacting with

The energy of the incoming photon is more than the ionisation energy of the atom it is interacting with

The energy of the incoming photon is greater than the ionisation energy of the atom it is interacting with

2.

1 point

The heaviest of the particle emissions are:

Gamma rays

Alpha particles

Neutrons

Beta particles

3.

1 point

Compton scattering results in the scattering of the incident photon, with the degree of scattering depended on:

Loss of energy

Density of interacting atom

Electron configuration

Atomic number of the interacting atom

4.

1 point

The inner envelope of an X-ray tube is usually made from:

Lead

Borosilicate glass

Aluminium

Perspex

5.

1 point

What does keV stand for?

Kiloelectronvolt

Kineticenergyvolt

Kiloenergyvolt

Kineticenergyvelocity

6.

1 point

Dose equivalent is measured in:

Grays

Sieverts

Man sieverts

Coulombs

7.

1 point

Absorbed dose is measured in:

Man sieverts

Sieverts

Grays

Coulombs

8.

1 point

In diagnostic radiography, photoelectric absorption occurs greatest in:

Tissue

Fat

Bone

Air

9.

1 point

Elastic collisions of incoming electrons with atoms of the x-ray target:

Produce heat and light

Involve transfer of energy to the target

Produce x-ray photons

Rarely occur

10.

1 point

Exposure is measured in:

Coulombs per kg

Coulombs per mg

Sieverts per cGy

Coulombs per mGy

11.

1 point

In diagnostic radiography the principle attenuation process is:

Unmodified scatter

Compton scatter

Photoelectric absorption

Pair production

12.

1 point

Under the Ionising radiation regulations (IRR 99) the annual dose limit for an adult worker is:

50 mSv

20 mSv

5 mSv

2 mSv

13.

1 point

A K-alpha transition:

Results in the emission of characteristic radiation

Results in the emission of bremsstrahlung

Results in excitation

Is the ionisation of a K shell electron

14.

1 point

A Geiger-Muller counter measures:

Electronic pulses

The arrival of individual photons of ionising radiation or high energy particles

The incidence of light

The incidence of heat

15.

1 point

The added filtration of a diagnostic X-ray tube typically consists of:

Aluminium or Beryllium

Aluminium or Copper

Copper or Tin

Tin or Lead

16.

1 point

Which of the following is NOT a form of energy?

Magnetism

Kinetic

Electricity

Chemical

17.

1 point

The effective dose from a PA chest examination is typically:

20 mSv

2 mSv

0.02 mSv

0.2 mSv

18.

1 point

Modern anode discs, which contain more than one material in their construction may be referred to as a:

Rare earth anode

Double anode

Bi-anode

Compound anode

19.

1 point

The half life of an radionuclide is 5 days. If the initial activity was 100 MBq on the 5th day of the month, what will be its activity on the 15th day of that month:

12.5 MBq

50 MBq

75 MBq

25 MBq

20.

1 point

With regards to an increase in proton (atomic) number:

The incidence of Compton scattering increases rapidly

The incidence of photoelectric absorption increases rapidly

The incidence of photoelectric absorption decreases rapidly

The incidence of Compton scattering decreases rapidly

21.

1 point

Collisions of incoming electrons with bound electrons in the x-ray target may result in ionisation of the atom:

And subsequest fission

And gamma ray emission

And subsequent emission of alpha and beta particles

If the energy transferred exceeds the binding energy of the shell involved

22.

1 point

A controlled area may be defined as:

An area where instantaneous dose rate is greater than 75 micro Sv /hr

An area where instantaneous dose rate is greater than 7.5 micro Sv/hr

An area where instantaneous dose rate is less than 7.5 micro Sv /hr

An area where instantaneous dose rate is more than 0.75 micro Sv/hr

23.

1 point

Photographic film badge monitoring devices are unable to detect:

Gamma rays

Neutrons

X-rays

Beta particles

24.

1 point

The atomic number of Lithium Fluoride is approximately:

47

8

4

84

25.

1 point

Typical anode angles in general diagnostic X-ray tubes (excluding mammography) tend to be between:

25 – 28 degrees

15 – 17 degrees

20 – 25 degrees

4 - 6 degrees

26.

1 point

The filtration of an X-ray beam has the effect of:

Improving the quantity of the transmitted X-ray beam

Reducing the quantity and decreasing quality of the transmitted X-ray beam

Improving the quality of the transmitted X-ray beam

Improving the quality and increasing quantity of the transmitted X-ray beam

27.

1 point

Which of the following is NOT a requirement for an X-ray tube filament material?

High work function

High melting point

High atomic number

Ductile

28.

1 point

Radioactivity may be defined as:

A process whereby some nuclides undergo spontaneous changes in the structure of nuclei

A process whereby some nuclides undergo spontaneous changes in the structure of electrons

A process whereby some nuclides undergo spontaneous changes in the structure of neutrons

A process whereby some nuclides undergo spontaneous changes in the structure of protons

29.

1 point

When attenuated with filtration, the following aspect of an x-ray beam is improved:

Quality

Intensity

Mass attenuation coefficient

Intensity and Quality

30.

1 point

Electrical energy is:

Measured in coulombs

Created in an x-ray tube

Indicated by potential difference

Converted directly into heat and x-rays in an x-ray tube

31.

1 point

Bremsstrahlung radiation:

Has a maximum photon energy in keV numerically equal to the applied kVp

Is emitted when an incoming electron interacts with a bound electron

Is responsible for the line spectrum of x-rays emitted from the target

Is limited to specific x-ray photon energies

32.

1 point

A TLD monitoring device uses the following material to detect radiation:

Lithium Fluoride

Sodium Fluoride

Lithium Oxide

Lithium Halide

33.

1 point

In radiotherapy (over 1 MeV) the principle attenuation process is:

Pair production

Compton scatter

Unmodified scatter

Photoelectric absorption

34.

1 point

An electron accelerated through a pd of 50 000 volts will gain kinetic energy of:

50V

50 000V

50 KeV

50 000 kV

35.

1 point

Classified workers are workers where:

They are likely to exceed four tenths of the annual dose limit

They are likely to exceed three tenths of the annual dose limit

They are likely to exceed six tenths of the annual dose limit

They are likely to meet the annual dose limit

36.

1 point

The following material is added to the anode disc of a rotating X-ray tube to prevent the crazing effect:

Rhenium

Molybdenum

Carbon

Copper

37.

1 point

The temporary excited condition of a radionuclide is known as:

Fluorescent state

Isometric state

Metastable state

Positron state

38.

1 point

X-ray beams are always:

Heterogeneous

Characteristic

Homogeneous

Exponential

39.

1 point

One Gray of X-rays gives a dose equivalent of:

1 Sv

5 Sv

0.1 Sv

10 Sv

40.

1 point

Which unit allows the damage capability of a quantity of radiation to be expressed:

Grays

Sieverts

Man sieverts

Coulombs

41.

1 point

The expansion bellows performs the following task:

Provides additional X-ray production

Aids in the exposure timing

Permits greater heat capacity of the anode surface

Acts as a safety device within the X-ray tube

42.

1 point

Naturally occurring radioisotopes does not include:

Radium-226

Uranium-238

Technetium-99

Carbon-14

43.

1 point

Pair production can only take place when the photon energy:

Exceeds 1.02 MeV

Equal to 1.002 MeV

Exceeds 102 MeV

Is below 1.02 MeV

44.

1 point

With reference to the interaction of electrons (cathode) with atoms of the anode, what percentage of typically heat occurs?

0.1 percent

1 percent

10 percent

99 percent

45.

1 point

An electron accelerated through a potential difference gains:

Kinetic energy

Voltage

Heat

Potential Energy

46.

1 point

Increasing the kilovoltage setting for an exposure will:

Increase sharpness

Reduce skin dose

Reduce the skin dose and improve contrast

Increase skin dose and improve contrast

47.

1 point

An x-ray spectrum:

Gives the relative amount of all electromagnetic radiation emitted

Is not produced above keV

Gives the relative number of x-rays emitted at each photon energy

Is due to photoelectric absorption and Compton scatter

48.

1 point

As the photon energy of an x-ray beam increases:

The incidence of photoelectric absorption increases

The incidence of Compton scattering increases

the incidence of Compton scattering increases and Photoelectric absorption decreases

The incidence of Compton scattering and photoelectric absorption both decreases

49.

1 point

Stationary X-ray tubes are utilised mainly in:

Computerised Tomography

General X-ray rooms

Intra-oral X-ray units

Fluoroscopy rooms

50.

1 point

Dose area product (DAP) meters usually provide readings in:

Q x cm2

Ckg x cm2

cGy x cm2

mSv x m2