LRA 211 FINAL QUESTIONS & ANSWERS
Leakage radiation must not exceed - Answers - Less than 100 mR/hr
Size of target window - Answers - Usually 5cm squared
The x-ray tube is situated in a - Answers - Protective housing
The protective housing is made up of - Answers - -Lead lined structure
-Oil bath (99% heat, 1% x-ray)
-Cooling fans
-Electrical insulation
-Large cables
-Absorbs stray photons
What is the glass envelope made of - Answers - Borosilicate glass (pyrex) because it
is heat resistant
Anode - Answers - The anode is the positive end of the tube. It provides the target for
electron interaction to produce x-rays and is an electrical and thermal conductor.
Designed to dissipate heat
Tungsten - Answers - Has a high atomic number that can withstand heat
Stator - Answers
-The stator is made up of electromagnets arranged in pairs around the rotor. The stator
is outside the tube enclosure.
Rotor - Answers - The rotor is made of an iron core surrounded by coils and located in
the center of the stator but within the enclosure. The rotor does not touch the stator, nor
is it supplied with electric current. It is operated through mutual induction.
, Cathode - Answers - Negative end of the tube. It provides the source of electrons
needed for x-ray production. The cathode is made up of the filaments and the focusing
cup
Which component of the x-ray tube is responsible for concentrating the electron cloud -
Answers - Focusing cup
The x-ray tube is part of the - Answers - X-ray circuit secondary
Thermionic emission - Answers - The process of electrons being burned off of the
filament
What is the target window designed for - Answers - The desired exit point of the x-rays
produced. The target window is fashioned to minimally interfere with (absorb) the x-rays
The intensity of the x-ray beam is more - Answers - On the cathode side
What reduces leakage radiation to required standards - Answers - Protective housing
The term space charge within the x-ray tube refers to - Answers - Free electrons
What makes up the cathode - Answers - Dual-focus tubes (2 filaments)
Focusing cup
Molybdenum - Answers - Used as the disk base and core because it has a low thermal
conductivity and it is a light but strong alloy
A rotating anode is made up of - Answers - A rotating tungsten-coated (high atomic
number) molybdenum disc mounted on a copper shaft with a molybdenum core
Housing - Answers - A protective housing provides solid mechanical support
Electromagnetic radiation - Answers - A form of energy that originates from the atom,
can exist apart from matter and travel through a vacuum
The relationship between wavelength and frequency is - Answers - Inverse
Wavelengths are measured in - Answers - Meters, from crest to crest
Frequencies are measured in - Answers - Hertz, how many waves in a timeframe
Electromagnetic radiation is characterized by - Answers - How it interacts with matter
X-rays originate through - Answers - Interactions between electrons and atoms
Amplitude - Answers - Height of a wave
Leakage radiation must not exceed - Answers - Less than 100 mR/hr
Size of target window - Answers - Usually 5cm squared
The x-ray tube is situated in a - Answers - Protective housing
The protective housing is made up of - Answers - -Lead lined structure
-Oil bath (99% heat, 1% x-ray)
-Cooling fans
-Electrical insulation
-Large cables
-Absorbs stray photons
What is the glass envelope made of - Answers - Borosilicate glass (pyrex) because it
is heat resistant
Anode - Answers - The anode is the positive end of the tube. It provides the target for
electron interaction to produce x-rays and is an electrical and thermal conductor.
Designed to dissipate heat
Tungsten - Answers - Has a high atomic number that can withstand heat
Stator - Answers
-The stator is made up of electromagnets arranged in pairs around the rotor. The stator
is outside the tube enclosure.
Rotor - Answers - The rotor is made of an iron core surrounded by coils and located in
the center of the stator but within the enclosure. The rotor does not touch the stator, nor
is it supplied with electric current. It is operated through mutual induction.
, Cathode - Answers - Negative end of the tube. It provides the source of electrons
needed for x-ray production. The cathode is made up of the filaments and the focusing
cup
Which component of the x-ray tube is responsible for concentrating the electron cloud -
Answers - Focusing cup
The x-ray tube is part of the - Answers - X-ray circuit secondary
Thermionic emission - Answers - The process of electrons being burned off of the
filament
What is the target window designed for - Answers - The desired exit point of the x-rays
produced. The target window is fashioned to minimally interfere with (absorb) the x-rays
The intensity of the x-ray beam is more - Answers - On the cathode side
What reduces leakage radiation to required standards - Answers - Protective housing
The term space charge within the x-ray tube refers to - Answers - Free electrons
What makes up the cathode - Answers - Dual-focus tubes (2 filaments)
Focusing cup
Molybdenum - Answers - Used as the disk base and core because it has a low thermal
conductivity and it is a light but strong alloy
A rotating anode is made up of - Answers - A rotating tungsten-coated (high atomic
number) molybdenum disc mounted on a copper shaft with a molybdenum core
Housing - Answers - A protective housing provides solid mechanical support
Electromagnetic radiation - Answers - A form of energy that originates from the atom,
can exist apart from matter and travel through a vacuum
The relationship between wavelength and frequency is - Answers - Inverse
Wavelengths are measured in - Answers - Meters, from crest to crest
Frequencies are measured in - Answers - Hertz, how many waves in a timeframe
Electromagnetic radiation is characterized by - Answers - How it interacts with matter
X-rays originate through - Answers - Interactions between electrons and atoms
Amplitude - Answers - Height of a wave
