M14

Question 1

is an electronic vacuum tube with components contained within
a glass or metal enclosure.

Answer 1

An x-ray tube

Question 2

An x-ray tube contained in a ____ and rarely
seen by Radiologic Technologist.

Answer 2

protective housing

Question 3

The x-ray tube, however, is a special type of
vacuum tube that contains two electrodes:

Answer 3

the cathode and the anode.

Question 4

is the negative side of the x-ray tube;

Answer 4

The cathode

Question 5

Cathode has two primary parts

Answer 5

a
filament and a focusing cup

Question 6

An x-ray tube filament emits electrons when it is heated. When the current through the filament is sufficiently high, the outer-
shell electrons of the filament atoms are “boiled off” and ejected from the
filament. This phenomenon is known as

Answer 6

thermionic emission

Question 7

The cloud of electrons, called a_____ , makes it difficult for subsequent electrons to be emitted by the filament by electrostatic repulsion.

Answer 7

space charge

Question 8

The cloud of electrons, called a space charge, makes it difficult for subsequent electrons to be emitted by the filament by electrostatic repulsion. This phenomenon is called

Answer 8

This phenomenon is called
the space charge effect.

Question 9

Electrons traveling from cathode to anode constitute the x-ray tube current and
are sometimes called . When these projectile electrons hit
the heavy metal atoms of the x-ray tube target, they transfer their kinetic energy
to the target atoms.

Answer 9

projectile electrons

Question 10

The filament is embedded in a metal shroud called the _____; it electrostatically confines the electron beam (projectile electron) to a small area of the anode called the target.

Answer 10

focusing cup

Question 11

is the area of the anode struck by the electrons from the cathode.
The projectile electron interacts with the orbital electrons or the nuclear field of
target atoms. These interactions result in the conversion of electron kinetic
energy (heat) and electromagnetic energy in the form of infrared radiation (also
heat) and x-rays.

Answer 11

The target

Question 12

When an exposure is being made, x-ray radiation exits the tube as what is
known as

Answer 12

primary beam.

Question 13

When the primary beam passes through the body,
some of the radiation is absorbed in a process known as

Answer 13

attenuation

Question 14

The _____ beam is responsible for exposing the image receptor.

Answer 14

remnant

Question 15

is a type of secondary radiation that occurs when the
useful beam intercepts any object, causing some x-rays to be scattered. During
an x-ray or fluoroscopic exam, the patient is the most significant source of
scattered radiation.

Answer 15

Scattered radiation

Question 16

are all radiation escaping from within the source assembly
except for the useful beam. It is primarily controlled through the design of the
tube housing and proper collimator filtering.

Answer 16

Leakage radiation

Question 17

refers to emission of x-ray photons which originate outside
of the anode focal spot. Essentially a form of scatter, photons produced in this manner may result in blurring and are of no use for diagnostic purposes.

Answer 17

Off-focus radiation

Question 18

All of these x-
rays are called ____ because they result from electron transitions into the
K-shell.

Answer 18

K x-rays

Question 19

is a German word that means “slowed-down” radiation. Bremsstrahlung x-rays can
be considered radiation that results from the braking of projectile electrons by
the nucleus.

Answer 19

Bremsstrahlung