X-ray Production Study Questions

The kinetic energy of the projectile electron in an x-ray tube:

c.) Is about 1% efficient in the production of x-rays.

The shift of the characteristic x-ray spectrum to higher energy occurs because of which of the following?

e.) An increase in target atomic number.

Useful characteristic x-rays are produced in tungsten:.

b.) By removal of a K-shell electron.

An L-shell electron (binding energy 26 keV) is removed from an atom that has M-shell binding energy of 4 keV and N-shell binding energy of 1 keV. If a free electron fills the vacancy in the L-shell, the characteristic x-ray produced will have energy of:

e.) 26 keV

What is produced when the projectile electron excites an outer-shell electron?

d.) Heat

The energy of characteristic x-rays increases with increasing:

c.) Atomic number of target material.

X-rays are produced when:

c.) Projectile electrons interact with target atoms.

Characteristic x-rays:

a.) Are characteristic of target Z.

When a tungsten-targeted x-ray tube is operated at 68 kVp:

d.) Some projectile electrons may have 68 keV of energy.

When characteristic x-rays are produced, the energy of the x-rays is characteristic of:

b.) The atomic number of the target.

Gold is sometimes used as target material in special types of radiation-producing systems. Its electron-binding energies are as follows: K-shell: 81 keV; L-shell: 14 keV; M-shell: 3 keV; and N-shell: 1 keV. Which of the following characteristic x-rays would be produced with operation at 90 kVp?

b.) 67 keV

The kinetic energy of a projectile electron can be measured in:

c.) Joules

The efficiency of x-ray production is:

d.) Independent of tube current.

The Joules (J) of energy generated by electron-target interactions is given by:

a.) kv x mA x s

In a tunsten-targeted x-ray tube operated at 90 kVp, the most abundant x-ray would be a:

c.) 30 keV Bremsstrahlung x-ray

Which of the following electron transitions results in the most useful Bremsstrahlung x-ray?

e.) None of the above

Bremsstrahlung radiation is produced by:

a.) Conversion of projectile electron kinetic energy to electromagnetic energy.

When a Bremsstrahlung x-ray is produced:

b.) A projectile electron loses energy.

In Bremsstrahlung x-ray production:

B.) The projectile electron is from the cathode.

If an average radiographic technique is used:

d.) Most x-rays are Bremsstrahlung.

Bremsstrahlung x-rays are produced only at:

d.) Energies up to projectile electron energy.

If radiographic technique is 74 kVp/80 mAs:

a.) Bremsstrahlung x-ray energy increases if the voltage is increased to 84 kVp.

If radiographic technique is a tungsten target as 60 kVp/80 mAs is changed to 80 kVp/80 mAs:

e.) The number of x-rays produced increases.

Bremsstrahlung x-rays produced in a tungsten targeted x-ray tube:

e.) Outnumber characteristic x-rays.

When a Bremsstrahlung x-ray is emitted:

d.) This results from the conversion of kinetic energy.

The wavelength of an x-ray:

a.) Becomes longer with increasing projectile electron energy.

When projectile electron energy is increased:

c.) More Bremsstrahlung x-rays are produced.

The efficiency of Bremsstrahlung x-ray production increases with increasing:

e.) Target atomic number

The output intensity of an x-ray tube:

e.) Is primarily due to Bremsstrahlung x-rays.

Which of the following projectile electron-target interactions results in x-ray emission?

c.) Removal of inner-shell electron.

When a projectile electron enters a target atom and interacts with the nuclear force field:

a.) It decreases in velocity.

In a tungsten-targeted x-ray tube operated at 90 kVp, the most abundant x-ray would be a:

c.) 30 keV bremsstrahlung x-ray

The area under the curve of the x-ray emission spectrum represents:

d.) The total number of x-rays.

Normally the x-ray emission spectrum contains:

a.) Both characteristic and bremsstrahlung x-rays.

The characteristic x-ray emission spectrum principally depends on which of the following?

e.) Target material

The continuous x-ray emission spectrum principally depends on which of the following?

d.) Projectile electron energy.

Which of the following factors explains the low number of x-rays emitted at low energy?

a.) Added filtration

The x-ray emission spectrum represents:

e.) X-ray emitted from the x-ray tube.

Both the shape and the position of the characteristic x-ray emission spectrum:

d.) Correspond to target electron binding energies.

A diagnostic x-ray beam contains:

b.) Mostly Bremsstrahlung x-rays, with some characteristic x-rays.

The x-ray emission spectrum is a plot of:

c.) The number of x-rays versus energy.

The amplitude of the Bremsstrahlung x-ray emission spectrum:

c.) Has maximum value at energy at one third of the kVP.

If an x-ray emission spectrum represented operation at 85 kVp with a tungsten target:.

c.) The K-characteristic x-ray emission would occur at 69 keV.

If an x-ray emission spectrum represented operation at 26 kVp with a molybdenum target:

c.) The characteristic radiation would have an energy of approximately 10 keV.

Which of the following factors principally accounts for the reduced x-ray intensity at low energy?

a.) Added filtration.

Characteristic x-radiation is related to the:

b.) Energy required to eject K-shell electrons.

Molybdenum has a lower atomic number than tungsten; therefore, the molybdenum x-ray emission spectrum:

e.) Has lower amplitude.

To construct an x-ray emission spectrum, one must know the:

c.) Number of x-rays at each energy interval.

Which characteristic is reduced as x-ray energy increases?

e.) X-ray wavelength.

The wavelength of an x-ray is:

e.) Inversely proportional to its energy.

The product of the Planck constant (h) and the velocity of light (c) equals:

a.) 12.4 eVm

b.) 12.4 keVm

c.) 12.4 x 10*-7 eVm

d.) 12.4 x 10*-10 eVm

e.) 12.4 x 10*-15 eVm

c.) 12.4 x 10*-7 eVm

Minimum wavelength is related to:

d.) The kinetic energy of the projectile electron.

That region of the x-ray emission spectrum associated with minimum wavelength is the:

a.) Highest energy bremsstrahlung x-ray.

If one knows the minimum wavelength of an x-ray emission spectrum, one can calculate:

e.) Maximum projectile electron energy.

To calculate minimum x-ray wavelength, one must know the value of:

b.) kVp

At 80 kVp and 80 mAs, how would the total emission spectrum be affected by operation at 80 kVp/400 mA/100 ms? The relative position of the spectrum would:

c.) Remain the same, but the amplitude would increase.

How would the emission spectrum be affected by the addition of 2 mm Al filtration? The relative position of the spectrum would:

e.) Shift to the right, and the amplitude would be lower.

How would the emission spectrum be affected if the power supply were changed from single phase to three phase? The relative position of the spectrum would:

e.) Shift to the right, the amplitude would increase, and the characteristic lines would increase in height.

Which of the following statements applies to the x-ray emission spectrum?

d.) The target material affects the amplitude of bremsstrahlung x-rays.

An increase in mAs results in an increase in:

b.) Both characteristic and bremsstrahlung x-rays.

An increase in kVp results in an increase in:

d.) Radiation quality.

The intensity of x-ray exposure is best represented by:

d.) The area under the emission spectrum.

Which of the following factors primarily affects the low-energy side of the x-ray emission spectrum?

b.) Filtration

In general, when changes are made that affect the x-ray emission spectrum and the:

e.) Spectrum shifts to the right, a more penetrating beam is emitted.

How would the bremsstrahlung spectrum change if operation at 80 kVp/200 mA/100ms were changed to 64 kVp/200 mA/100 ms?

c.) It would shift to the left, and the amplitude would be lower.

How would the characteristic spectrum change if operation were at 64 kVp/200 mA/20 ms? The characteristic x-ray spectrum would:

b.) Disappear.