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27 Cards in this Set
- Front
- Back
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What are the four conditions that must be present for xrays to be produced?
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1. Source of electrons
2. Target 3. High Voltage 4. Vacuum |
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What side of the tube is negative?
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The cathode side
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What three things does the cathode consist of?
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The filament, the focusing cup, and the associated wiring.
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what is the thickness, width, and length, for the coil of the thoriated tungsten on the filament?
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.1-.2mm thick, 1-2mm wide, and 7-15 mm long.
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What does filament length and width impact?
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Recorded Detail
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Why is tungsten used for the filament material?
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High melting point and is difficult to vaporize
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What is the focal track made out of?
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Rhenium and molybdenum
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What happens during thermionic emission?
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filament is heated which causes electrons to be released from the filament
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What two things cause tube failure?
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Tube arcing and filament breakage. Tube arcing is caused from vaporized tungsten collected on the envelope
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What is the focusing cup made of?
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nickel
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Is the focusing cup positively charged or negatively?
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negative
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What does the focusing cup do?
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copresses the thermionic cloud
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What are the three fuctions of the anode assemby?
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1. Target Surface
2. Conduct high voltage 3. Primary thermal conductor |
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What are the three components of the anode assembly?
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anode, stator, and rotor
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What are the three reasons for tungsten being the metal of choice ?
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1. High atomic number
2. High melting point 3. Heat conducting ability |
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What does the back of the anode consist of?
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molybdenum and or graphite that assists with heat loading
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What are the three reasons for a warm up procedure?
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warming up the anode to prevent cracking, maintains the vacuum, and relieves stress on the anode
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What are the five portions of the anode that the electron stream contacts?
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The target, focus, focal point, focal spot, and focal track.
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Where is the point source of x-ray photons?
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Target
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The effective focal spot is controlled by what two things?
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The actual focal spot and the target angle
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What is another name for pnumbra?
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blur
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What is the anode hell effect?
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intensity is greater on the cathode side
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What does the stator run?
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the anode
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Where is the stator located?
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outside the glass envelope
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The stator is an induction motor of what that comprise the stator that turns the anode?
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electromagnets
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The stator is the only part of the cathode or anode that is located the vacuum of the envelope.
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Outside
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What happens when the stators fails?
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The anode melts
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