Radiation Physics

Question 1

matter

Answer 1

anything that occupies space and has mass

Question 2

atom

Answer 2

fundamental unit of matter

Question 3

nucleus

Answer 3

dense inner core composed of protons and neutrons

Question 4

electrons

Answer 4

negatively charged particles
travel around nucleus in paths known as orbits

Question 5

binding energy

Answer 5

attraction of positive protons to negative electrons
electrons are maintained in their orbits

Question 6

how are molecules formed

Answer 6

transfer of electrons
sharing of electrons

Question 7

ionization

Answer 7

production of ions

Question 8

ions

Answer 8

atoms that gain or lose an electron
electrically unbalanced
gains = negative charge
loses = positive charge

Question 9

non-ionizing radiation

Answer 9

does not have enough energy to create ions (microwaves, visible light)

Question 10

ionizing radiation

Answer 10

creates positive and negative ions as it travels and interacts with atom
radiation that produces ions (x-rays, gamma rays)

Question 11

electromagnetic radiation

Answer 11

moves through space as a particle and a wave
EM spectrum:
-travel at speed of light
-have no electrical charge
-have no mass or weight
-pass through space as particles in wavelike motion

Question 12

electromagnetic waves determine strength of radiation by:

Answer 12

velocity: speed of wave
wavelength: distance between crest of one wave and crest of the next
frequency: # of wavelengths that pass a point in a certain time

Question 13

frequency is ______ related to wavelength

Answer 13

inversely

Question 14

wavelength determines

Answer 14

energy and penetrating power of the radiation

Question 15

long wavelength =

Answer 15

low frequency
low energy
less penetrating x-ray

Question 16

short wavelength =

Answer 16

high frequency
high energy
more penetrating x-ray

Question 17

metal housing

Answer 17

surrounds x-ray tube and transformers
protects tube and grounds high-voltage components

Question 18

insulating oil

Answer 18

surrounds x-ray tube and transformers
prevents overheating

Question 19

tubehead seal

Answer 19

permits exit of x-rays from tubehead
seals the oil
filters x-ray beam

Question 20

x-ray tube

Answer 20

heart of generating system

Question 21

transformer

Answer 21

alters voltage of incoming electricity

Question 22

aluminum discs

Answer 22

filters out non-ionizing, longer wavelength x-rays

Question 23

lead collimator

Answer 23

restricts size of x-ray beam

Question 24

position-indicating device

Answer 24

aims and shapes the x-ray beam

Question 25

x-ray tube components

Answer 25

lead-glass housing
negative cathode
positive anode

Question 26

the cathode

Answer 26

negative electrode
tungsten filament
supplies electrons

Question 27

the anode

Answer 27

positive electrode
tungsten target embedded in copper stem
converts electrons into photons
tungsten target is focal point

Question 28

x-rays at the center of the anode beam are called

Answer 28

central ray

Question 29

focal spot

Answer 29

small rectangular area on target of anode
smaller focal spot = sharper image