M13

Question 1

were not developed; they were discovered, and quite by accidents.

Answer 1

X-rays

Question 2

During the , many university physics laboratories were investigating

Answer 2

1870s and 1880s

Question 3

the conduction of cathode rays, or electrons, through a large, partially evacuated glass tube. known as a

Answer 3

Crookes tube.

Question 4

was an Englishman from a rather humble background who was a self-taught genius.
The tube that bears his name was the forerunner of modern fluorescent lamps and x-ray tubes. There were many different types of Crookes tubes; most of them were capable of producing x-rays.

Answer 4

Sir William Crookes

Question 5

was experimenting with a type of Crookes tube when he
discovered x-rays.

Answer 5

Wilhelm Roentgen

Question 6

On _______ Roentgen was working in his
physics laboratory at Wurzburg University in
Germany. He had darkened his laboratory and
completely enclosed his Crookes tube with black
photographic paper so he could better visualize the
effects of the cathode rays in the tube.

Answer 6

November 8, 1895,

Question 7

The intensity of the glow increased as the plate was brought closer to the tube; consequently, there was little doubt about the origin of the stimulus of the glow.This glow is

Answer 7

fluorescence.

Question 8

In ____ he received the first Nobel Prize in Physics. Roentgen
recognized the value of his discovery to medicine.

Answer 8

1901

Question 9

He produced and published
the first medical x-ray image in ____. It was an image of his wife’s hand.

Answer 9

1896.

Question 10

There are three general types of x-ray examinations:

Answer 10

radiography, fluoroscopy,
and CT.

Question 11

Early radiographic procedures often required exposure times of _____ or
longer.

Answer 11

30 minutes

Question 12

Long exposure time results in

Answer 12

image blur

Question 13

One development that helped
reduce this exposure time was the use of fluorescent _______ in conjunction with the glass photographic plates.

Answer 13

intensifying screen

Question 14

is said to have demonstrated the use of a radiographic intensifying screen in 1896, but only many years later did it receive adequate
recognition and use.

Answer 14

Michael Pupin

Question 15

Radiographs during Roentgen’s time were made by exposing a _____ with a layer of photographic emulsion coated on one
side.

Answer 15

glass plate

Question 16

found that by exposing two glass x-ray plates with the
emulsion surfaces together, exposure time was halved, and the image was
considerable enhanced. This demonstration of double-emulsion radiography
was conducted in 1904, but double emulsion film did not become commercially available until 1918.

Answer 16

Charles L. Leonard

Question 17

Much of the high-quality glass used in radiography came from _______. This supply was interrupted during World War I;
therefore, radiologists began to make use of film rather than glass plates.

Answer 17

Belgium and
other European countries

Question 18

The demands of the army for increased radiologic services made necessary a
substitute for the glass plate. The substitute was ______ and it quickly
became apparent that the substitute was better than the original plate.

Answer 18

cellulose nitrate

Question 19

was developed in 1898 by the American inventor Thomas A.
Edison.

Answer 19

The fluoroscope

Question 20

Edison’s original fluorescent material was ______, a widely-used laboratory material. He investigated the fluorescent properties of
more than 1800 other materials, including zinc cadmium sulphide and calcium
tungstate – two materials in use today.

Answer 20

barium platinocyanide

Question 21

There is no telling what additional inventions Edison might have developed had
he continued his x-ray research, but he abandoned it when his assistant and
long-time friend,______ , experienced a severe x-ray burn that eventually required amputation of both arms.

Answer 21

Clarence Dally

Question 22

Dally died in _____ and is counted
as the first x-ray fatality in the United States.

Answer 22

1904

Question 23

In 1907, H.C. Snook introduced a substitute high-
power supply, an interupterless transformer, for the static machines and
induction coils then in use.
Although the Snook transformer was far superior to these other devices, its
capability greatly exceeded the capability of the Crookes tube. It was not until
the introduction of the ______ that the Snook transformer was widely
adopted.

Answer 23

Coolidge tube

Question 24

 X-rays are invisible

Answer 24

True

Question 25

 X-rays are not electrically neutral

Answer 25

False, They made neither a positive nor a negative charge, therefore they cannot
be accelerated or made to change direction by a magnet or electrical field.

Question 26

 X-rays have mass

Answer 26

False, X-rays have no mass
They create no resistance to being put into motion and cannot produce
force.

Question 27

X-rays travel at the speed of light in a vacuum
They move at a constant velocity of 3.0 x 108 m/s or 186,000 mi/s in a
vacuum.

Answer 27

True

Question 28

X-rays canbe optically focused

Answer 28

False, cannot be, Optical lenses have no ability in focusing or refracting x-ray photons.

Question 29

 X-rays form a polyenergetic or heterogeneous beam

Answer 29

True, The x-ray beam that is used in diagnostic radiography is composed of
photons that have different energies. The maximum energy that a photon in
any beam have is expressed by the kilovoltage peak (kVp) that is set on the
control panel of the radiographic unit by the radiographer.
 X-rays can be produced in a range of energies
X-rays can be produced in a range of energies that is useful for different
purposes in diagnostic radiography. The medically useful diagnostic range
of x-ray energies extend up to 25 to 150 kVp.

Question 30

 X-rays travel in a parallel line

Answer 30

False, X-rays travel in a straight line
X-rays used in diagnostic radiography form a divergent beam which each
individual photons travel in a straight line.

Question 31

 X-rays cause some substances to fluoresce
When x-rays strike substances, those substances produce light. These
substances are used in diagnostic radiography, in intensifying screens, and
in image intensifiers used in fluoroscopy.

Answer 31

True

Question 32

X-rays does not cause chemical changes to occur in radiographic and photographic
film

Answer 32

False, X-rays are capable of causing images to appear in radiographic film and are
capable of fogging the photographic film.

Question 33

X-rays cannot penetrate the human body

Answer 33

False, X-rays have the ability to pass through the body, based on the energy of the
x-rays and on the composition and thickness of the tissues being exposed.

Question 34

X-rays cannot be absorbed or scattered (attenuated) in the human body

Answer 34

False, Depending on the energy of an individual x-ray photon, that photon may be
absorbed in the body or be made to scatter, moving in another direction.

Question 35

X-rays can produce secondary radiation

Answer 35

True, When x-rays are absorbed as a result of specific type of interaction with
matter, the photoelectric effect, a secondary or characteristic photon will be
produced.

Question 36

 X-rays can cause chemical and biologic damage to living tissue

Answer 36

True, Through excitation and ionization of atoms comprising cells, damage to
those cells can occur.