CAMRT Xray Physics + Principles Exam
Questions and Answers with Verified
Solutions | Latest Updated 2026
electrons are produced at the a. cathode
a. cathode Thermionic emission occurs -- x-ray
b. anode filament is
heated, boils off electrons
Electrons travel to anode (+) target,
gaining kinetic
energy
99% electrons dissipate as heat, 1% emits
as
Bremsstrahlung or characteristic radiation
______% electrons dissipate as d. 99
heat
a. 10
b. 1
c. 50
d. 99
for imaging the proximal femur, stomach
should the cathode side be thicker area = need more photons!
towards
the stomach or the knee?
most emitted xrays are... a. Bremsstrahlung
a. Bremsstrahlung
b. Characteristic
,anode target atom is made of c. tungsten
a. molybdenum
b. rhodium
c. tungsten
d. a and c
_______ SQUARE LAW INVERSE
What: As distance ↑, intensity ↓ by
4x
Used: Calculating the relationship
between distance and x-ray
intensity
(mR)
high signal correlates to d. all the above
a. darker area also kVp amount:
b. low atomic number Higher energy photons are more
c. low attenuation penetrating,
d. all the above leading to less attenuation
, ______ Contrast c. subject
Definition: Relative magnitude of Factors Affecting Subject Contrast
differences within the remnant -Non-uniformity of object
beam --Thickness
exiting the object due to density Thicker = higher chance of attenuation
differences (photons
As ___(same)___ contrast ↑, absorbed)
signal Thinner = lower chance of attenuation
difference between object edges ↑ (photons
a. low pass)
b. image --Density
c. subject High density = higher chance of
d. a and b attenuation
Low density = Photons easily pass
--Atomic number
As atomic number ↑, nucleus size ↑,
number of
electrons in atom ↑, attenuation ↑
-Beam energy (kVp)
As energy (kVp) ↑, photon penetrability ↑
⇒ lower
contrast
ability to capture small structures c. spatial resolution
adjacent to each other as distinct
entities (e.g. microcalcifications)
a. constrast resolution
b. high resolution DR system
c. spatial resolution
d. CT resolution
Questions and Answers with Verified
Solutions | Latest Updated 2026
electrons are produced at the a. cathode
a. cathode Thermionic emission occurs -- x-ray
b. anode filament is
heated, boils off electrons
Electrons travel to anode (+) target,
gaining kinetic
energy
99% electrons dissipate as heat, 1% emits
as
Bremsstrahlung or characteristic radiation
______% electrons dissipate as d. 99
heat
a. 10
b. 1
c. 50
d. 99
for imaging the proximal femur, stomach
should the cathode side be thicker area = need more photons!
towards
the stomach or the knee?
most emitted xrays are... a. Bremsstrahlung
a. Bremsstrahlung
b. Characteristic
,anode target atom is made of c. tungsten
a. molybdenum
b. rhodium
c. tungsten
d. a and c
_______ SQUARE LAW INVERSE
What: As distance ↑, intensity ↓ by
4x
Used: Calculating the relationship
between distance and x-ray
intensity
(mR)
high signal correlates to d. all the above
a. darker area also kVp amount:
b. low atomic number Higher energy photons are more
c. low attenuation penetrating,
d. all the above leading to less attenuation
, ______ Contrast c. subject
Definition: Relative magnitude of Factors Affecting Subject Contrast
differences within the remnant -Non-uniformity of object
beam --Thickness
exiting the object due to density Thicker = higher chance of attenuation
differences (photons
As ___(same)___ contrast ↑, absorbed)
signal Thinner = lower chance of attenuation
difference between object edges ↑ (photons
a. low pass)
b. image --Density
c. subject High density = higher chance of
d. a and b attenuation
Low density = Photons easily pass
--Atomic number
As atomic number ↑, nucleus size ↑,
number of
electrons in atom ↑, attenuation ↑
-Beam energy (kVp)
As energy (kVp) ↑, photon penetrability ↑
⇒ lower
contrast
ability to capture small structures c. spatial resolution
adjacent to each other as distinct
entities (e.g. microcalcifications)
a. constrast resolution
b. high resolution DR system
c. spatial resolution
d. CT resolution
