Principles of Radiographic Imaging I Test 1 Practice Questions

What is the primary reason x-ray tubes are enclosed in a vacuum?

A. Allow free electron flow without resistance

B. Maintain anode rotation

C. Prevent radiation leakage

D. Minimize characteristic radiation

A. Allow free electron flow without resistance

Which of the following significantly affects the quantity of x-rays produced?

A. Kilovoltage peak (kVp)

B. Filtration

C. Milliampere-seconds (mAs)

D. Anode angle

C. Milliampere-seconds (mAs)

What is the primary purpose of beam filtration in diagnostic radiography?

A. Increase patient dose

B. Improve spatial resolution

C. Eliminate scatter radiation

D. Remove low-energy photons

D. Remove low-energy photons

What happens to x-ray beam quality when kVp is increased?

A. It decreases

B. It increases

C. It remains the same

D. It becomes more heterogeneous

B. It increases

Which of the following is most responsible for controlling beam penetrability?

A. kVp

B. Focal spot size

C. Exposure time

D. mA

A. kVp

Which of the following is a valid formula for calculating mAs?

A. mAs = kVp × seconds

B. mAs = mA ÷ seconds

C. mAs = mA × seconds

D. mAs = distance × mA

C. mAs = mA × seconds

Which statement is true regarding low-energy photons?

A. They increase patient dose

B. They decreases patient dose

C. They contribute to image formation

D. They increase beam quality

A. They increase patient dose

What is the Half-Value Layer (HVL) used to determine?

A. mAs accuracy

B. Exposure time

C. Beam quantity

D. Beam quality

D. Beam quality

According to NCRP Report #102, what is the minimum total filtration required for equipment operated at or above 70 kVp?

A. 1.5 mm Al

B. 2.0 mm Al

C. 2.5 mm Al

D. 3.0 mm Al

C. 2.5 mm Al

What effect does increasing aluminum filtration have on the x-ray beam?

A. Decreases quantity and increases quality

B. Increases both quantity and quality

C. Increases quantity and decreases quality

D. Increases scatter radiation

A. Decreases quantity and increases quality

What describes the line-focus principle?

A. Relationship between kVp and mAs

B. Relationship between actual and effective focal spot

C. Relationship between filtration and HVL

D. Relationship between anode and cathode intensity

B. Relationship between actual and effective focal spot

X-ray intensity is greater on which side of the x-ray tube due to the anode heel effect?

A. Anode side

B. Central ray

C. Filtration side

D. Cathode side

D. Cathode side

What is the effect of increasing mAs on the x-ray beam?

A. Increases quantity only

B. Increases both quality and quantity

C. Increases quality only

D. Decreases beam divergence

A. Increases quantity only

Which of the following occurs at the cathode side during preparation for exposure?

A. Characteristic interaction

B. Rotor rotation

C. Electron deceleration

D. Thermionic emission

D. Thermionic emission

The projectile electron must possess a minimum of how many keV to produce characteristic x-rays in tungsten?

A. 69.5 keV

B. 70.5 keV

C. 75.0 keV

D. 65.0 ke

A. 69.5 keV

Which unit measures absorbed dose in tissue?

A. Roentgen

B. Sievert

C. Gray

D. Becquerel

C. Gray

Which interaction accounts for the majority of the diagnostic x-ray beam?

A. Photoelectric

B. Bremsstrahlung

C. Pair production

D. Characteristic

B. Bremsstrahlung

What type of transformer is used to increase voltage to kilovoltage levels?

A. Step-down

B. Autotransformer

C. Capacitor

D. Step-up transformer

D. Step-up transformer

X-ray tube current is measured in which unit?

A. Amperes

B. Volts

C. Milliamperes-second

D. Milliamperes

D. Milliamperes

The "space charge effect" limits the number of what?

A. Electrons emitted from the filament

B. X-ray photons produced

C. Photons reaching the detector

D. Voltage across the anode

A. Electrons emitted from the filament

What is the typical energy range for diagnostic x-rays?

A. 1-10 keV

B. 15-150 keV

C. 200-500 keV

D. 0.5-1 MeV

B. 15-150 keV

How much does Bremsstrahlung interaction accounts for when the x-ray beam is above 70 kVp?

A. 85%

B. 90%

C. 95%

D. 100%

A. 85%

How much does Bremsstrahlung interaction accounts for when the x-ray beam is below 70 kVp?

A. 85%

B. 90%

C. 95%

D. 100%

D. 100%

What does the line-focus principle improve in radiographic imaging?

A. Contrast resolution

B. Beam divergence

C. Temporal resolution

D. Spatial resolution

D. Spatial resolution

Which part of the x-ray tube absorbs most, if not all, of the leakage radiation?

A. Focusing cup

B. Tube housing

C. Filtration system

D. Image receptor

B. Tube housing

What best defines the Half-Value Layer (HVL)?

A. Thickness of filter that absorbs all x-rays

B. Measurement of inherent filtration

C. Thickness of material that reduces beam intensity by 50%

D. Standard for output reproducibility

C. Thickness of material that reduces beam intensity by 50%

Which component allows technologists to select the desired kVp?

A. Autotransformer

B. Rectifier

C. Step-up transformer

D. Capacitor

A. Autotransformer

Which of the following improves both x-ray beam quality and patient safety?

A. Anode rotation

B. Filtration

C. mAs

D. Exposure time

B. Filtration

What happens when a bremsstrahlung interaction occurs close to the nucleus?

A. Characteristic radiation is produced

B. Photon is absorbed

C. Low-energy photon is emitted

D. High-energy photon is emitted

D. High-energy photon is emitted

Which of the following increases beam quality and reduces beam quantity?

A. Increasing filtration

B. Decreasing kVp

C. Increasing mAs

D. Decreasing exposure time

A. Increasing filtration

What should a radiographer do to extend tube life?

A. Use short exposure times with high mA

B. Avoid warming up the tube

C. Hold the rotor for extended time

D. Use low mA with longer exposure times

D. Use low mA with longer exposure times

What is the purpose of the focusing cup?

A. Heat absorption

B. Shield leakage radiation

C. Concentration of electrons

D. Rotate the anode

C. Concentration of electrons

What best describes electromagnetic radiation used in x-ray imaging?

A. Exhibits wave-particle duality

B. Moves slower than sound waves

C. Has mass and charge

D. Only behaves like a particle

A. Exhibits wave-particle duality

What are the three main components needed for x-ray production?

A. A vacuum, rotating anode, and step-down transformer

B. Source of electrons, target, and high voltage

C. Collimator, filter, and housing

D. kVp, SID, and grid

B. Source of electrons, target, and high voltage

What is the function of the autotransformer in the x-ray circuit?

A. Converts AC to DC

B. Regulates filament current

C. Adjusts kVp settings

D. Measures exposure time

C. Adjusts kVp settings

In a characteristic interaction, if a K-shell electron is replaced by an L-shell electron, what determines the photon energy?

A. The difference in shell binding energies

B. The number of electrons in the atom

C. The speed of the projectile

D. The target angle

A. The difference in shell binding energies

What happens when the prep (rotor) button is pressed?

A. The image is stored

B. The filament heats and the target begins spinning

C. The anode cools down

D. The x-ray beam is immediately produced

B. The filament heats and the target begins spinning

What determines the speed of electrons in the tube current?

A. mA

B. Exposure time

C. Anode angle

D. Kilovoltage (kVp)

D. Kilovoltage (kVp)

Increasing exposure time will:

A. Increase x-ray quality

B. Increase the effective focal spot size

C. Increase x-ray quantity

D. Increase anode rotation

C. Increase x-ray quantity

A small anode angle results in:

A. Larger effective focal spot

B. Smaller effective focal spot

C. More off-focus radiation

D Poorer spatial resolution

B. Smaller effective focal spot

The anode heel effect results in:

A. More intense beam on the cathode side

B. More intense beam on the anode side

C. Higher patient dose

D. Uniform x-ray beam intensity

A. More intense beam on the cathode side

Where should the thicker body part be placed during an exposure using the anode heel effect?

A. Under the anode

B. Under the cathode

C. Away from the central ray

D. It does not matter

B. Under the cathode

If mA is doubled and time remains the same, what happens to the x-ray quantity?

A. Doubles

B. Remains the same

C. Decreases by half

D. Quadruples

A. Doubles

What part of the anode is struck by the electron stream?

A. Effective focal spot

B. Filament

C. Rotor

D. Actual focal spot

D. Actual focal spot

What happens to spatial resolution with a smaller effective focal spot?

A. Decreases

B. Increases

C. Remains unchanged

D. Increases contrast

B. Increases

What is the main benefit of warming up the x-ray tube?

A. Reduces scatter

B. Prevents tube cracking

C. Increases radiation output

D. Shortens exposure time

Prevents tube cracking

The focusing cup has a __________ charge.

A. Positive

B. Negative

C. Neutral

D. Variable

B. Negative

What is produced at the anode during exposure?

A. Heat only

B. Scatter radiation only

C. X-rays and heat

D. Characteristic x-rays only

C. X-rays and heat

Which term describes the graphic representation of x-ray photon energy levels produced during exposure?

A. X-ray emission spectrum

B. Tube current graph

C. Half-value curve

D. Characteristic interaction map

A. X-ray emission spectrum

The energy range for diagnostic x-rays in the emission spectrum typically begins at approximately:

A. 1-5 keV

B. 10-15 keV

C. 15-20 keV

D. 30-35 keV

B. 10-15 keV

What defines the actual focal spot in the x-ray tube?

A. Area viewed from the central ray

B. Region where filtration is thickest

C. Projected image of the anode

D. Spot where tube current strikes the target

D. Spot where tube current strikes the target

A disadvantage of using high mA and short exposure time repeatedly is:

A. Less sharp images

B. Anode heel effect

C. Risk of overheating the tube

D. Longer processing time

C. Risk of overheating the tube

Which of the following interactions results in the emission of x-rays when an outer-shell electron fills an inner-shell vacancy?

A. Bremsstrahlung

B. Photoelectric

C. Compton

D. Characteristic

D. Characteristic

Which of the following statements best describes bremsstrahlung radiation?

A. It occurs when a projectile electron dislodges an inner-shell electron.

B. It is produced when the projectile electron slows down near the nucleus.

C. It only occurs when electrons are completely absorbed.

D. It is responsible for a small percentage of the diagnostic x-ray beam.

B. It is produced when the projectile electron slows down near the nucleus.

What is the primary reason for using a rotating anode in diagnostic x-ray tubes?

A. Improve spatial resolution

B. Reduce exposure time

C. Shorten the wavelength

D. Increase heat capacity

D. Increase heat capacity

The relationship between tube current (mA) and x-ray quantity is:

A. Directly proportional

B. Inversely proportional

C. No effect

D. Indirectly proportional

A. Directly proportional