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单选题

The voltage and waveform applied to the X-ray tube by a high-voltage transformer primarily determines the _____.

A. quantity of radiation
B. duration of exposure
C. penetrating ability
D. X-ray beam divergence

单选题

A thin metallic sheet (brass, copper, aluminum, etc) placed at the source to reduce effects of softer radiation is known as _____.

A. an intensifying screen
B. a filter
C. beam collimator
D. a focusing cup

单选题

To produce X-rays, electrons are accelerated to a high velocity by an electrical field and then suddenly stopped by a collision with a solid body. This body is called ______.

A. Cathode
B. Filament
C. Target
D. generator

单选题

The reason for using a rotating anode is_____.

A. to reduce heating on the filament
B. to increase radiation output
C. to keep the effective focus small
D. a combination of B and C

单选题

The maximum energy of the X-ray quanta is determined by____.

A. Tube voltage kV
B. Dose rate mAs
C. Tube current mA
D. filament current

单选题

What’s the function of the radial slots in the anode?

A. to let the anode cool down quickly
B. to hold the cooling oil
C. to relief the mechanical stress
D. to ease the anode manufacture

单选题

Tungsten is selected to be the anode material because_____.

A. its low atomic number to the efficiency of radiation production
B. its high hardness to be bombard
C. its high melting point to the power rating
D. it’s easy to be manufactured

单选题

Which of following materials is not used within an X-ray tube?

A. Rhenium
B. Radium
C. Tungsten
D. Graphite

单选题

Stationary X-ray tubes are normally utilized in the following applications except____.

A. Dental examination
B. Hand/foot examination
Computerized Tomography
D. Portable units

单选题

Regarding geometric unsharpness, which of the following is false?

A. Inversely proportional to focal spot size
B. Directly proportional to object-film distance.
C. Inversely proportional to focal spot-object distance.
D. Characterized by penumbra width.

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