Chapter 5 Test

Question 1

Radiation with suffiecient energy to detach an electron from an atom describes:

a.) radiation therapy
b.) electromagnetic radiation
c.) ionizing radiation
d.) ion pair

Answer 1

c.) ionizing radiation

Question 2

To help dissipate heat produced during xray production, the xray tube housing is filled with:

a.) oil
b.) water
c.) air
d.) tungsten

Answer 2

a.) oil

Question 3

Which component maintaisn a vaccuum to protect from an xray tube from arcing and interacting with current electrons?

a.) anode
b.) tube envolope
c.) tube housing
d.) cathode

Answer 3

b.) tube envelope

Question 4

What is the purpose of the glass or metal envelope? Choose all that apply.

a.) to create a vacuum
b.) to cushion the xray tube
c.) to prevent interaction between the electron stream and air electrons
d.) as an electrical insulator

Answer 4

a.) to create a vacuum
c.) to prevent interaction between the electron stream and air electrons

Question 5

Xray photon intensity is less on the:

a.) cathode side of the tube
b.) anode side of the tube

Answer 5

b.) anode side of the tube

Question 6

As the anode target angle increases:

a.) kvp increases
b.) effective focal spot size increases
c.) radiation intensity on the central ray increases
d.) target rotating speed increases
e.) heel effect becomes more pronounced

Answer 6

b.) effective focal spot size increases

Question 7

The purpose of the line focus principle is to create which of the following?

a.) small actual and large effective focal spot size
b.) large actual and small effective focal spot size
c.) large actual and effective focal spot size
d.) small actual and effective focal spot size

Answer 7

b.) large actual and small effective focal spot size

Question 8

Rotating anodes in general use radiography, rotate at approximately:

a.) 3400 rpm
b.) 2400 rpm
c.) 1000 rpm
d.) 10000 rpm

Answer 8

a.) 3400 rpm

Question 9

Photons are created when electrons interact a target made of copper.

a.) true
b.) false

Answer 9

b.) false

Question 10

What is the atomic number of tungsten?

Answer 10

74

Question 11

A small anoed angle will do which of the following?

a.) increase SP by creating a small effective focal spot
b.) increase heat dissipation due to a larger surface area being bombarded by electrons
c.) increase image receptor exposure because of a lack of electron abdsorbtion from the anode
d.) decrease SR by creating a large effective focal spot

Answer 11

a.) increase SR by creating a small effective focal spot

Question 12

When kvp is applied (rotor) there is a potential difference created in the xray tube. Electrons are then sent from anode to cathode.

a.) true
b.) false

Answer 12

b.) false

Question 13

Electrodynamics is also known as “electricity”.

a.) true
b.) false

Answer 13

a.) true

Question 14

To take advantage of the anode heel effect, the thicker part of a patient should be placed where?

a.) anode side
b.) cathode side

Answer 14

b.) cathode side

Question 15

Most electrical energy in the xray tube is converted to:

Answer 15

heat

Question 16

Which part of an induction motor is located within the xray tube glass envelope?

a.) stator
b.) rotor
c.) filament
d.) focusing cup

Answer 16

b.) rotor

Question 17

In xray production the electrons stream of effective focal spot is the stream projected toward the patient.

a.) true
b.) false

Answer 17

b.) false

Question 18

xrays are produced:

a.) in one direction
b.) anisotropically
c.) isotropically

Answer 18

c.) isotropically

Question 19

According to the basic principle of radiation protection, a radiographer should minimize what?

a.) sheilding
b.) time
c.) distance
d.) patient protection

Answer 19

b.) time

Question 20

The stream projected towrad the anode is called:

a.) imaging spot
b.) actual focal spot
c.) target
d.) effectivec focal spot

Answer 20

b.) actual focal spot

Question 21

The ampere is the unit of measure for:

a.) resistance
b.) electrostatics
c.) electric current
d.) electric potential

Answer 21

c.) electric current

Question 22

In xray production, electrons travel at the speed of light inside a vacuum tube.

a.) true
b.) false

Answer 22

b.) false

Question 23

What is the most common target angle on anode?

Answer 23

12 degrees

Question 24

Two filaments in one xray tube is called:

a.) diode tube
b.) multi focus tube
c.) dual focus tube
d.) effective focal track

Answer 24

c.) dual focus tube

Question 25

Who discovered xrays?

Answer 25

Wilhelm Roentgan

Question 26

Which of the following anode angles will produce the highest spatial resolution?

a.) 6
b.) 24
c.) 12
d.) 8

Answer 26

a.) 6

Question 27

A large anode angle will cause which of the following: choose all that apply

a.) an increase in image receptor exposure
b.) a decrease in spatial resolution
c.) an increased heel effect
d.) a decrease in heat dissipation

Answer 27

a.) an increase in image receptor
b.) a decrease in spatial resolution

Question 28

Small anode target angles result in which of the following?

a.) less heel effect
b.) increased heat caparcity
c.) small focus spot size
d.) better collimation

Answer 28

c.) small focus spot size

Question 29

Anode angle will have an effect on the:

1.) severity of the heel effect
2.) focal spot size
3.) heat-load capacity

a.) 1, 2 and 3
b.) 1 only
c.) 2 only
d.) 1 and 2 only

Answer 29

a.) 1, 2 and 3

Question 30

The heel effect occurs because of:

a.) the shape charge effect
b.) reduced tube current
c.) the shape of the filament
d.) a focusing cup
e.) xray absorption in the anode

Answer 30

e.) xray absorption in the anode

Question 31

Choose all that apply.

a.) xrays travel at 1/2 speed of light
b.) xrays are electrically neutral, therefore unaffected by electric or magnetic fields
c.) xrays can ionize matter
d.) xrays release small amounts of heat when passing through matter

Answer 31

b.) xrays are electrically neutral, therefore unaffected by electric or magnetic fields
c.) xrays can ionize matter
d.) xrays release small amounts of heat when passing throguh matter

Question 32

Which xray tube component is located outside of the metal or glass envelope?

a.) rotor
b.) anode
c.) cathode
d.) stators

Answer 32

d.) stators

Question 33

The purpose of the envelope is to maintain a vacuum inside the tube so the electron stream is not disrupted.

a.) true
b.) false

Answer 33

a.) true

Question 34

The xray tube consist of which of the following? choose all that apply.

a.) anode
b.) cathode
c.) lead housing
d.) induction motor

Answer 34

a.) anode
b.) cathode
d.) induction motor

Question 35

Approxiamtely what percentage of electrons are converted to heat during xray production?

a.) 99 percent
b.) 50 percent
c.) 1 percent
d.) 10 percent

Answer 35

a.) 99 percent

Question 36

The cathode has what type of charge?

Answer 36

negative

Question 37

What percentage of electrons is converted to xray photons?

Answer 37

less than 1 percent

Question 38

Leakage radiation in an xray tube must not exceed:

Answer 38

100 mR/hr per meter

Question 39

The filament is made of

Answer 39

tungsten

Question 40

As a waves wavelength increases, its frequency:

a.) depends on the type of EMR
b.) decreases
c.) stays the same
d.) increases

Answer 40

b.) decreases

Question 41

The cathode assembly consists of which of the following?

a.) stator, rotor, target angle
b.) shutters, mirror, light source
c.) filament and focusing cup
d.) filament, focusing cup, tungesten target

Answer 41

c.) filament and focusing cup

Question 42

What formula would be used to determine the total number of heat units produced with a given exposure using three phase 12 pulse equipment?

Answer 42

mA x time x kV x 1.41

Question 43

Which of the following devices converts mechanical energy into electrical energy?

a.) motor
b.) generator
c.) stator
d.) rotor

Answer 43

b.) generator

Question 44

One main reason for the line focus principle is:

a.) increase xray intensity
b.) reduce exposure time
c.) reduce focal spot size
d.) increase heat capacity
e.) reduce heel effect

Answer 44

c.) reduce focal spot size

Question 45

in the xray circuit, which transformer does voltage travel through first

a.) mutual induction transformer
b.) autotransformer
c.) step up transformer
d.) step down transformer

Answer 45

b.) autotransformer

Question 46

The area of the anode bombarded by electrons is called:

a.) effective focal spot
b.) actual focal spot

Answer 46

b.) actual focal spot

Question 47

When using high technique settings, which cathode filament will be automatically seleceted?

a.) small filament
b.) large filament
c.) both filaments

Answer 47

b.) large filaments

Question 48

a small anode angle results in:

a.) decreased anode heel effect
b.) increased anode heel effect

Answer 48

b.) increased anode heel effect

Question 49

The tube head assembly consists of:

a.) tube stand
b.) all of the above
c.) collimator
d.) xray tube

Answer 49

b.) all of the above

Question 50

Rotating anodes have a higher heat load capacity than stationary anodes.

a.) true
b.) false

Answer 50

a.) true

Question 51

In most xray tubes, there are two filament to

Answer 51

provide two focal spots

Question 52

Which of the following mat cause potential damage to an xray anode? choose all that apply.

a.) high maximum exposure factors
b.) long low exposures
c.) excessive rotoring
d.) silmutaneously pressing the exposure and rotor button

Answer 52

a.) high maximim exposure factors
b.) long low exposures
c.) excessive rotoring

Question 53

As electrons collide with the anode surface, less than 1 percent of their kinetic energy is changed to:

a.) gamma rays
b.) xrays
c.) recoil electrons
d.) heat

Answer 53

b.) xrays

Question 54

An atom in a normal state has an electrical charge of __________

a.) one
b.) zero
c.) positive
d.) negative

Answer 54

b.) zero

Question 55

When will the space charge be present in an xray tube?

a.) while rotoring
b.) after pressing the exposure button all the way down
c.) before rotoring

Answer 55

a.) while rotoring

Question 56

The line focus principle expresses the relationship between

a.) SID used and resulting receptor exposure
b.) the actual end and effective focal spot
c.) exposure given the IR and resulting receptor exposure
d.) grid ratio and lines per inch

Answer 56

b.) the actual and effective focal spot

Question 57

What is the focusing cup made of?

a.) polyester
b.) nickle
c.) molybdenum
d.) tungsten

Answer 57

b.) nickle

Question 58

ALl of the following are associated with the anode except:

a.) the focal track
b.) thermionic emmision
c.) the heel effect
d.) the line focus principle

Answer 58

b.) thermionic emmision

Question 59

What is the function of the xray tube housing? choose all that apply.

a.) acts as a thermal cusion for the xray tube
b.) is an electrical insulator
c.) helps to block leakage radiation
d.) creates a vacuum for electrons

Answer 59

a.) acts as a thermal cushion for the xray tube
b.) is an electrical insulator
c.) helps to block leakage radiation

Question 60

The relationship between the anode heel effect and the andoe angle is:

a.) direct
b.) indirect

Answer 60

b.) indirect

Question 61

ALl of the electromagnetic radiatons are capable of ionizing matter

a.) true
b.) false

Answer 61

b.) false