Chapter 5 Test Flashcards
Radiation with suffiecient energy to detach an electron from an atom describes:
a.) radiation therapy
b.) electromagnetic radiation
c.) ionizing radiation
d.) ion pair
c.) ionizing radiation
To help dissipate heat produced during xray production, the xray tube housing is filled with:
a.) oil
b.) water
c.) air
d.) tungsten
a.) oil
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
b.) tube envelope
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
a.) to create a vacuum
c.) to prevent interaction between the electron stream and air electrons
Xray photon intensity is less on the:
a.) cathode side of the tube
b.) anode side of the tube
b.) anode side of the tube
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
b.) effective focal spot size increases
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
b.) large actual and small effective focal spot size
Rotating anodes in general use radiography, rotate at approximately:
a.) 3400 rpm
b.) 2400 rpm
c.) 1000 rpm
d.) 10000 rpm
a.) 3400 rpm
Photons are created when electrons interact a target made of copper.
a.) true
b.) false
b.) false
What is the atomic number of tungsten?
74
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
a.) increase SR by creating a small effective focal spot
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
b.) false
Electrodynamics is also known as “electricity”.
a.) true
b.) false
a.) true
To take advantage of the anode heel effect, the thicker part of a patient should be placed where?
a.) anode side
b.) cathode side
b.) cathode side
Most electrical energy in the xray tube is converted to:
heat
Which part of an induction motor is located within the xray tube glass envelope?
a.) stator
b.) rotor
c.) filament
d.) focusing cup
b.) rotor
In xray production the electrons stream of effective focal spot is the stream projected toward the patient.
a.) true
b.) false
b.) false
xrays are produced:
a.) in one direction
b.) anisotropically
c.) isotropically
c.) isotropically
According to the basic principle of radiation protection, a radiographer should minimize what?
a.) sheilding
b.) time
c.) distance
d.) patient protection
b.) time
The stream projected towrad the anode is called:
a.) imaging spot
b.) actual focal spot
c.) target
d.) effectivec focal spot
b.) actual focal spot
The ampere is the unit of measure for:
a.) resistance
b.) electrostatics
c.) electric current
d.) electric potential
c.) electric current
In xray production, electrons travel at the speed of light inside a vacuum tube.
a.) true
b.) false
b.) false
What is the most common target angle on anode?
12 degrees
Two filaments in one xray tube is called:
a.) diode tube
b.) multi focus tube
c.) dual focus tube
d.) effective focal track
c.) dual focus tube
Who discovered xrays?
Wilhelm Roentgan
Which of the following anode angles will produce the highest spatial resolution?
a.) 6
b.) 24
c.) 12
d.) 8
a.) 6
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
a.) an increase in image receptor
b.) a decrease in spatial resolution
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
c.) small focus spot size
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
a.) 1, 2 and 3
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
e.) xray absorption in the anode
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
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
Which xray tube component is located outside of the metal or glass envelope?
a.) rotor
b.) anode
c.) cathode
d.) stators
d.) stators
The purpose of the envelope is to maintain a vacuum inside the tube so the electron stream is not disrupted.
a.) true
b.) false
a.) true
The xray tube consist of which of the following? choose all that apply.
a.) anode
b.) cathode
c.) lead housing
d.) induction motor
a.) anode
b.) cathode
d.) induction motor
Approxiamtely what percentage of electrons are converted to heat during xray production?
a.) 99 percent
b.) 50 percent
c.) 1 percent
d.) 10 percent
a.) 99 percent
The cathode has what type of charge?
negative
What percentage of electrons is converted to xray photons?
less than 1 percent
Leakage radiation in an xray tube must not exceed:
100 mR/hr per meter
The filament is made of
tungsten
As a waves wavelength increases, its frequency:
a.) depends on the type of EMR
b.) decreases
c.) stays the same
d.) increases
b.) decreases
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
c.) filament and focusing cup
What formula would be used to determine the total number of heat units produced with a given exposure using three phase 12 pulse equipment?
mA x time x kV x 1.41
Which of the following devices converts mechanical energy into electrical energy?
a.) motor
b.) generator
c.) stator
d.) rotor
b.) generator
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
c.) reduce focal spot size
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
b.) autotransformer
The area of the anode bombarded by electrons is called:
a.) effective focal spot
b.) actual focal spot
b.) actual focal spot
When using high technique settings, which cathode filament will be automatically seleceted?
a.) small filament
b.) large filament
c.) both filaments
b.) large filaments
a small anode angle results in:
a.) decreased anode heel effect
b.) increased anode heel effect
b.) increased anode heel effect
The tube head assembly consists of:
a.) tube stand
b.) all of the above
c.) collimator
d.) xray tube
b.) all of the above
Rotating anodes have a higher heat load capacity than stationary anodes.
a.) true
b.) false
a.) true
In most xray tubes, there are two filament to
provide two focal spots
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
a.) high maximim exposure factors
b.) long low exposures
c.) excessive rotoring
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
b.) xrays
An atom in a normal state has an electrical charge of __________
a.) one
b.) zero
c.) positive
d.) negative
b.) zero
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
a.) while rotoring
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
b.) the actual and effective focal spot
What is the focusing cup made of?
a.) polyester
b.) nickle
c.) molybdenum
d.) tungsten
b.) nickle
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
b.) thermionic emmision
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
a.) acts as a thermal cushion for the xray tube
b.) is an electrical insulator
c.) helps to block leakage radiation
The relationship between the anode heel effect and the andoe angle is:
a.) direct
b.) indirect
b.) indirect
ALl of the electromagnetic radiatons are capable of ionizing matter
a.) true
b.) false
b.) false
