FREE RADIOLOGY AND STUDY GAMES ABOUT RAD121

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FREE RADIOLOGY AND STUDY GAMES ABOUT RAD121

EXAM QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -116 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: Housing Cooling Chart

Answer:

Permits the calculation of the time necessary for the housing to cool enough for additional exposures to be made Question 2: What materials, other than tungston, could be used to make the filament?

Answer:

Rhenium and molybdenum

Question 3: Anode Cooling Chart

Answer:

Permits the calculation of the time necessary for the anode to cool enough for additional exposures to be taken.

Question 4: Focal Point

Answer:

The portion of the anode where the high-voltage electron stream will impact; also: target, focus, focal spot, actual focal spot

Question 5: The focusing cup has what electrical charge?

Answer:

negative

Question 6: Stationary Anode

Answer:

An anode assembly that is immobile

Question 7: Envelope

Answer:

The entire cathode and anode assembly is housed within this glass or metal structure

Question 8: What must x-rays be a part of to be considered useful?

Answer:

the primary beam

Question 9: Off-Focus Radiation

Answer:

Photons created somewhere in the tube other than the focal spot; can cause ghosting; not a result of scatter from patient; exit through tube window

Question 10: Focusing Cup

Answer:

A shallow depression in the cathode assembly designed to house the filament

Question 11: How would a Rhenium Tungston alloy be used?

Answer:

As anode target material.

Question 12: Space Charge Cloud

Answer:

The ejection of electrons from the surface of the wire due to increased heat, causing an electron cloud;

also: thermionic emission, electron cloud

Question 13: What are 2 causes of tube failure?

Answer:

--1.tube arcing--2.filament breakage

Question 14: Protective Housing

Answer:

The entire cathode and anode assembly is housed within this metal structure

Question 15: What are rotating anode disks composed of?

Answer:

Molybdenum with the target focal track material being rhenium-alloyed tungsten backed by a thicker layer of molybdenum or graphite.

Question 16: What is the primary function of the envelope?

Answer:

To maintain the vacuum.

Question 17: Dual Focus

Answer:

A two-filament arrangement within the x-ray tube.

Question 18: Where is the window on the envelope?

Answer:

Where the primary beam exits.

Question 19: Target

Answer:

The portion of the anode where the high-voltage electron stream will impact; also: target, focus, focal spot, actual focal spot

Question 20: Harmonics

Answer:

Name of the tone a high-speed rotating cuff makes at 5000-7000 rpm capable of shattering the glass envelope.

Question 21: Anode Heel Effect

Answer:

Due to the geometry of the angled anode target, the radiation intensity is greater(20% more) on the cathode side; 25% fewer photons on anode side

Question 22: Filament

Answer:

A small coil of thin thoriated tungsten wire

Question 23: Define leakage radiation.

Answer:

Any photon that escapes from the housing except at the port.Question 24: Why is molybdenum used as the primary target material for mammography x-ray tubes?

Answer:

It's ability to emit a more uniform range of lower energy photons which permit better soft tissue imaging.

Question 25: What is a common cause of tube failure?

Answer:

Bad bearings because of long use at high temperatures.

Question 26: Where are grid-biased tubes found?

Answer:

capacitor discharge units and angiography units

Question 27: Anode Assembly

Answer:

Consists of the anode, stator, and rotor

Question 28: What is filament width?

Answer:

1-2 mm