Exam 1 Ch 4-

Question 1

continuum-

Answer 1

-continuous ordered sequence
-always present around us in some form

Question 2

continuum examples-

Answer 2

-free flowing river & sidewalks
-if a river is damned or sidewalk curves, then continuum is interrupted

Question 3

only part of a continuum we are naturally aware of-

Answer 3

visible light

Question 4

continuum goes from ________ to ________-

Answer 4

from long-wave radio waves to mega-volt therapy gamma rays

Question 5

greeks called an atom of light-

Answer 5

photon

Question 6

photon-

Answer 6

-smallest quantity of EMR
-can be referred to as photon radiation

Question 7

x-ray photons-

Answer 7

quantum of electromagnetic energy

Question 8

photons have no-

Answer 8

mass or identifiable form

Question 9

photons have-

Answer 9

electric & magnetic fields continuously changing in sinusoidal fashion

Question 10

amplitude-

Answer 10

1/2 range from crest to valley, over which sine waves vary

Question 11

gravity is an example of-

Answer 11

force we can’t see, but know exists

Question 12

velocity-

Answer 12

all EMR travels at the speed of light

Question 13

sinusoidal-

Answer 13

-S-wave pattern
-mathematically describable

Question 14

field-

Answer 14

describes interactions b/w energies/force that can’t be seen

Question 15

frequency-

Answer 15

number of wavelengths that passes a point of observation per second

Question 16

frequency aka-

Answer 16

-oscillations per second
-cycles per second

Question 17

frequency measured in-

Answer 17

-hertz
-Hz = # of cycle per second

Question 18

frequency w: EMR-

Answer 18

as frequency increases, wavelength decreases

Question 19

wavelength-

Answer 19

-distance from 1 crest to another/1 valley to another
-any point on a sine wave to the next corresponding point

Question 20

3 wave parameters-

Answer 20

-velocity
-frequency
-wavelength
-needed to describe electromagnetic energy

Question 21

wave equation-

Answer 21

velocity = frequency X wavelength (used for both sound & electromagnetic energy)

Question 22

frequency range-

Answer 22

10^2 to 10^24 Hz

Question 23

electromagnetic spectrum includes-

Answer 23

entire range of EMR

Question 24

3 regions of the electromagnetic spectrum most important to rad. techs.-

Answer 24

-visible light
-radiofrequency
-radiation

Question 25

visible light measured in-

Answer 25

meters

Question 26

radiofrequency measured in-

Answer 26

Hertz

Question 27

radiation measured in-

Answer 27

electron volts (eV)

Question 28

visible light described in-

Answer 28

terms of wavelength

Question 29

visible light travels-

Answer 29

-in a straight line
-course can deviate when they pass from one transport medium to another

Question 30

refraction-

Answer 30

deviation in the visible lights line of travel

Question 31

white light-

Answer 31

composed of photons of range of wavelength

Question 32

visible light is the smallest segment of-

Answer 32

electromagnetic spectrum

Question 33

radio frequency described in-

Answer 33

frequency

Question 34

radio frequency broadcasting varies as-

Answer 34

as the frequency varies in this portion of the spectrum

Question 35

radio frequency has-

Answer 35

-relatively low energy
-relatively long energy

Question 36

x-ray & gamma radiation are characterized by-

Answer 36

energy contained in a photon

Question 37

in ionizing radiation, operating consoles operate at-

Answer 37

80 kVp

Question 38

ionizing radiation produces-

Answer 38

contained energies ranging from 0-80 KeV

Question 39

only difference b/w x-rays & gamma rays is-

Answer 39

their origin

Question 40

x-rays originate-

Answer 40

outside the nucleus

Question 41

gamma rays originates-

Answer 41

within the nucleus

Question 42

photons interact w: matter most easily when-

Answer 42

matter is appx. the same size as the photons wavelength

Question 43

in a photon interaction, radio & TV waves measured in-

Answer 43

meters (long rods)

Question 44

in a photon interaction, visible light is measured in-

Answer 44

nanometers (living cells)

Question 45

in a photon interaction, microwaves measured in-

Answer 45

food items

Question 46

in a photon interaction, ultraviolet light measured in-

Answer 46

molecules

Question 47

in a photon interaction, x-rays measured in-

Answer 47

atoms/electrons

Question 48

visible light photons travel in ______ & interact w: ________-

Answer 48

-travel in wave form
-interact w: matter like waves

Question 49

x-rays travel in ______ & interact w: ________-

Answer 49

-travel in wave form
-interacts w: matter like particles

Question 50

wave mode- visible light-

Answer 50

-very narrow portion of the electromagnetic spectrum
-acts like x-ray in how it travels, but interacts w: matter like particles

Question 51

visible light behaves like-

Answer 51

waves

Question 52

in visible light, the light absorbed is converted to-

Answer 52

heat

Question 53

visible light 3 degrees of interactions-

Answer 53

-transparent
-translucent
-opaque

Question 54

radiopaque-

Answer 54

absorbs x-rays

Question 54

attenuate x-rays-

Answer 54

transmit x-rays

Question 55

raidoparent-

Answer 55

x-rays transmitted almost unimpeded

Question 56

inverse square law can be applied to-

Answer 56

point source or linear source (past 7x its length)

Question 57

intensity from the source decreases rapidly as-

Answer 57

the distance to the source increases

Question 58

the decrease in intensity is inversely proportional to-

Answer 58

the square of distance from the source to the object

Question 59

light & x-ray exhibit-

Answer 59

the inverse square law

Question 60

to apply the inverse square law-

Answer 60

-one must know 3 of the 4 parameters (2 distances & 2 intensities)
-L1/L2 = (D2^2/D1)^2

Question 61

mass equivalent of an electron-

Answer 61

0.51 MeV

Question 62

diagnostic range w: mammo-

Answer 62

25 kVp - 150 kVp

Question 63

diagnostic range w/o mammo-

Answer 63

45 kVp - 60 kVp