Lecture 4

Question 1

DISCOVERY OF X-RAYS

Answer 1

Wilhelm Konrad Roentgen November 8, 1895. The discovery took place in Dr. Roentgen’s physics laboratory at the University of Wurzburg, Germany.

Question 2

DISCOVERY OF X-RAYS

Shortly after the discovery, the medical field recognized x-rays as a valuable diagnostic tool, especially for detecting skeletal fractures. X-rays became essential in diagnosing diseases, and treatment of tumors.

Answer 2

Medical recognition and use

Question 3

CHARACTERISTICS OF X-RAY

Answer 3

Electromagnetic Radiation: X-rays are a form of electromagnetic radiation, part of a spectrum that includes visible light.

Wavelength and Energy: X-rays have a significantly shorter wavelength and greater energy compared to visible light.

Wave-like Motion: X-ray photons travel in a wave-like motion through air or matter.

Question 4

Ionizing Radiation and Safety Guidelines

X-radiation can ionize tissue,
causing

Answer 4

Biologic changes

Question 5

Ionizing Radiation and Safety Guidelines

Operators of
radiographic equipment must follow guidelines to prevent unnecessary exposure and protect patients and radiology personnel from the dangers
of ionizing radiation.

Answer 5

Importance of guidelines

Question 6

Protection Measures for Radiographers

Answer 6

-Limit time
-increase distance
-use shielding

Question 7

Rules of Time, Distance, and Shielding:
* : Use the shortest possible exposure time.

Answer 7

Time

Question 8

Rules of Time, Distance, and Shielding:

• : Always stand behind a shield containing
  the prescribed amount of lead or lead equivalent.

Answer 8

Shielding

Question 8

Rules of Time, Distance, and Shielding:

• : Maintain the longest distance possible
  from the source of x-rays.

Answer 8

Distance

Question 9

Most radiographic
departments are designed to accommodate
these basic rules.

Answer 9

Department Design

Question 10

By adhering to these
rules, radiographers can expect to be
protected from exposure to ionizing
radiation.

Answer 10

Adherence to rules

Question 11

X-ray photons are to the human
eye

Answer 11

Invisible

Question 11

As x-rays travel through air, they ionize it,
producing an electrical charge. This makes the
photons detectable by ionization chambers, which
measure the ions produced.
IC – to detect # xray photons

Answer 11

Ionization

Question 12

X-ray photons travel at the speed of light,
approximately 3 x 10^8 m/sec.

Answer 12

Speed

Question 13

X-ray photons travel in
straight lines and diverge from their point of
origin.

Answer 13

Straight-line travel

Question 14

X-ray photons cannot be
deflected by mirrors or other devices.

Answer 14

Non-deflectability

Question 15

X-ray photons cannot be focused by a lens,
as with .

Answer 15

Photography

Question 16

X-ray photons travel in straight lines and
diverge from the .

Answer 16

Point of origin

Question 17

X-ray photons cannot be deflected by
or other devices.

Answer 17

Mirrors

Question 18

When x-ray photons STRIKE CERTAIN SUBSTANCES,
visible light is emitted. This is called

Answer 18

Luminescence

Question 19

X-ray photons will cause changes to occur in the
of photographic film.

Answer 19

Sensitive emulsion

Question 20

When x-radiation interacts with matter,
radiation and radiation are produced

Answer 20

Secondary, scatter

Question 21

When x-ray photons strike certain
substances, visible light is emitted, a phenomenon
known as .

Answer 21

Luminescence

Question 22

X-ray photons cause
changes in the sensitive emulsion of photographic
film

Answer 22

Photographic Effects

Question 23

Interaction with
matter produces
radiation and
radiation.

Answer 23

Secondary and scatter radiation

Question 24

X-ray photons cannot be focused by
a lens, unlike visible light used in photography

Answer 24

Inability to focus

Question 25

– Magnification, Elongation and
Foreshortening

Answer 25

Recorded detail

Question 26

Shorter the wavelength the the frequency. It is inversely proportional

Answer 26

Higher

Question 27

Frequency and energy . It is directly proportional

Answer 27

Goes up/Increase/higher

Question 28

Increase in Energy and shorter wavelength is inversely proportional

Answer 28

Only energy wavelength is inversely proportional and frequency and energy is the only directly proportional

Question 29

2 chemicals that are used for processing latent image to visible image -

Answer 29

Developer and fixer

Question 30

SID - SOURCE TO IMAGE DISTANCE, FAR has great image
OID - OBJECT TO IMAGE, NEAR has great image
SOD - SOURCE TO OBJECT, FAR has great image

Answer 30

Only OID has great image in near

Question 31

Gurney mott theory

Answer 31

Formation of latent image

Question 32

When x-rays strike
substances inside film holders, such as intensifying
screen phosphors, they produce light

Answer 32

Intensifying Screen Phosphors

Question 33

Heart of radiographic or x-ray film

Answer 33

Emulsion

Question 34

Role of Light: This light plays a crucial role in exposing
the sensitive film emulsion, enhancing the action of
the x-rays.

Answer 34

Light = xray film (emulsion) latent image
(chemicals) = visible image

Question 35

_: The
object exposed to x-radiation
becomes a source of scatter
and secondary
_.

Answer 35

Source of radiation, rays

Question 36

__: Radiographers
and other personnel must
protect themselves from
scatter and secondary radiation
using lead barriers, such as
leaded glass or lead-lined walls
and doors.

Answer 36

Lead barriers