MCQs For The 1st FRCR

Question 1

An alpha particle has twice the mass of a proton.

Answer 1

False

Question 2

A proton has a mass approximately 1850 times that of an electron

Answer 2

True

Question 3

Regarding secondary electrons They cause tissue heating

Answer 3

True Energy from x-ray beam is converted into increased molecular motion and therefore heat

Question 4

Regarding ionizing radiation. Always obeys the inverse square law

Answer 4

False Only applicable to types of electromagnetic radiation from a point source and without attenuation.

Question 5

Regarding electromagnetic radiation. includes beta radiation.

Answer 5

False Beta particles are electrons emitted from nucleus.

Question 6

In radioactive decay, most nuclides left in a metastable state after beta decay, emit gamma rays to reach ground state.

Answer 6

True Isomeric transition.

Question 7

Regarding radioactivity! If stored long enough, the radioactivity of radionuclide will drop to zero

Answer 7

True Although decay is exponential process, all of the atoms will eventually decay.

Question 8

Regarding radioactivity! Decay constant is the probability of nuclear decay per unite time.

Answer 8

True

Question 9

Ragarding radionuclides! in 10 half-lives the activity is reduced by a factor of approximately 1000

Answer 9

True 10 half lives indicates decay by a factor of 2^10 or 1024

Question 10

Concerning properties of x-rays. Beam intensity is the total energy per unit area per unit time.

Answer 10

True this is the energy fluence rate or intensity.

Question 11

Concerning an x-ray tube! The angle of the target ensures that all x-rays produced pass through the window in the tube to from a beam

Answer 11

Flase X-rays will produced in many directions but only those that pass through the window will contribute to the useful beam, the others will be absorbed by the tube housing.

Question 12

X-ray producing in diagnostic x-ray tube occurs when moving electrons interact with target nuclei

Answer 12

True continuous spectrum radiation (Bremsstrahlung) is produced through electron- nucelues interactions and characteristic radiation is produced through electron-electron interactions within the target

Question 13

in a diagnostic x-ray tube: The anode stem is a poor heat conductor

Answer 13

True Prevents damage to the rotor assembly.

Question 14

in a diagnostic x-ray tube the anode angle: is generally 20-35^*

Answer 14

False The angle is generally 7-20^*

Question 15

in a diagnostic x-ray tube the anode angle: Determines the size of field covered by x-ray beam at a given focus-film distance.

Answer 15

True The steeper the angle the narrower the x-ray beam and the smaller field covered.

Question 16

Regarding an x-ray filament: It must have a high melting point and low resistance

Answer 16

False High melting point and high resistance to generate heat for theromionic emission.

Question 17

Regarding an x-ray filament: Tungsten is used because of its high atomic number

Answer 17

False This is the reaseon that is chosen for anode.

Question 18

The spectrum of an x-ray beam: Varies with tube current.

Answer 18

False increasing mA merely increasing the number of photons. Their energy and therefore the shape of the spectrum remains the same if kV is unaltered.

Question 19

The anode -heel effect: is greater if the target angle is steeper

Answer 19

True The steeper the target, the further through the target material the photons on the anode side of the beam have to travel and more attenuated they are.

Question 20

Regarding radioactive decay Half life is directly proportional to decay constant

Answer 20

False Inversly proportional