chapter 8 & 9 ( x ray production and emission )

Question 1

A change in_____
has no effect on the position of the discrete x-ray emission spectrum.

Answer 1

a.kVp
b.mAS
c.filtration
d.waveform

(All of the above)

Question 2

A compensating filter is used with a body part of_____
thickness to create______
optical density in the image.

Answer 2

non-uniform, uniform

Question 3

Added filtration results in_____

Answer 3

a.reduced X-ray quantity
b. an increase in the quality of the beam c.increased HvL
d. reduced patient dose

(All of the above)

Question 4

A filtered diagnostic X-Ray beam at 80 kVp contains

Answer 4

mostly bremsstrahlung, with some characteristic X-Rays

Question 5

A minimum HVL is required for diagnostic X-Ray beams because

Answer 5

a lower HVL would result in an increased absorbed dose to the patient with no improved image quality

Question 5

An exposure taken at 100 kVp would have a maximum energy of
keV.

Answer 5

100

Question 6

An exposure taken at 100 kVp would have an average energy of about
keV.

Answer 6

33

Question 7

An exposure taken at 100 kVp would have an effective characteristic X-Ray energy of
keV.

Answer 7

70

Question 8

An increase in kVp would_____
the______
of the emission spectrum

Answer 8

increase, amplitude and peak location (shift right)

Question 9

Approximately_______
of the kinetic energy of the projectile electrons is converted to X-Rays at the target.

Answer 9

1%

Question 10

An X-Ray beam can be made to have higher average energy if which of the following occurs?

Answer 10

Filtration is added

Question 11

As filtration is_____
beam quality is_______
and quantity is______

Answer 11

increased, increased, decreased

Question 12

As the number of pulses in the generator voltage waveform
the _______amplitude of the X-Ray spectrum________
and the peak shifts to the_____

Answer 12

increases, increases, right

Question 13

Changes in______
result in directly proportional changes in only the amplitude of the emission spectrum

Answer 13

mAs

Question 14

Characteristic X-Rays_____

Answer 14

are electromagnetic radiation

Question 15

Characteristic X-Rays are produced when

Answer 15

a vacancy in the electron orbit is filled

Question 16

Characteristic x-rays energies are directly affected by:

Answer 16

Target material (Z)

Question 17

Electron interactions at the inner shell of the target atoms produce______
radiation.

Answer 17

characteristic

Question 18

Factors that can change the X-Ray spectrum are all of the following except

Answer 18

focal spot

Question 19

How does an increase in filtration affect the emission spectrum?

Answer 19

reduced amplitude and a shift to the right

Question 20

If filtration is removed from the X-Ray beam, then the HVL

Answer 20

decreases

Question 21

If the distance from the source of X-Rays is increased by a factor of two, how is the X-Ray intensity at the image affected?

Answer 21

It is reduced by a factor of four

Question 22

If the kVp is increased, then the HVL

Answer 22

increases

Question 23

If the mAs is increased, then the HVL

Answer 23

stays the same

Question 24

If the technique changed from 80 kVp to 65 kVp, you would expect the peak of the bremsstrahlung spectrum to

Answer 24

shift to the left and decrease in amplitude

Question 25

If the tube is brought closer to the patient and the technique is not changed, then the HVL

Answer 25

stays the same

Question 26

If X-Ray quantity is increased, what happens to the digital image?

Answer 26

It becomes better or clearer

Question 27

Increasing the_____ in digital imaging, ______ the image contrast

Answer 27

mAs, does not increase

Question 28

Inherent filtration______

Answer 28

slightly increases over the tube's lifetime

Question 29

In order for a characteristic X-Ray to be produced, the energy must be______ the binding energy of the inner shell electron.

Answer 29

greater than

Question 30

lonization occurs due to

Answer 30

coulombic repulsion

Question 31

Penetrability of an X-Ray beam describes X-Ray

Answer 31

quality

Question 32

The 2nd HVL for a monoenergetic beam is______ the 1st HVL.

Answer 32

equal to

Question 33

The 2nd HVL for polyenergetic beam is______ the 1st HVL.

Answer 33

greater than

Question 34

The bremsstrahlung process produces X-Rays when

Answer 34

electrons are slowed in the anode

Question 35

The efficiency of X-Ray production slightly increases as_____ increases.

Answer 35

kVp

Question 36

The HVL is____

Answer 36

the thickness of a material to reduce the beam intensity to half the initial intensity

Question 37

The main purpose of added filtration is to reduce____

Answer 37

patient dose

Question 38

The number of useful X-Rays in the beam defines X-Ray

Answer 38

quantity

Question 39

The useful characteristic X-Rays in diagnostic radiology are from tungsten targets are_____ X-Rays.

Answer 39

K-shell

Question 40

The X-Ray emission______ is a plot of______

Answer 40

spectrum, number of X-Rays vs energy

Question 41

The X-Ray quality is____

Answer 41

not related to mAs

Question 42

The X-Ray quality______ when distance_____

Answer 42

does not change, is changed

Question 43

The X-Ray quality______ when kVp____

Answer 43

decreases,decreases

Question 44

The X-Ray quantity is___

Answer 44

directly related to mAs

Question 45

The X-Ray quantity is

Answer 45

directly related to kVp^2

Question 46

The X-Ray quantity is

Answer 46

inversely related to distance^2

Question 47

What happens to X-Ray penetrability as beam quantity increases?

Answer 47

Nothing, quantity is not effected by penetrability.

Question 48

When comparing the emission spectra of molybdenum with tungsten, both at 80 kVp and 20 mAs:

Answer 48

molybdenum characteristic X-Rays will have lower energies than tungsten

Question 49

Where are the lowest energy X-Rays that are produced most likely to be absorbed?

Answer 49

in the tube target

Question 50

Which clinical X-Ray exam is likely to have Characteristic X-Rays in the useful beam?

Answer 50

Chest x rays

Question 51

Which interaction involves production of Bremsstrahlung X-Rays?

Answer 51

Radiative

Question 52

Which interaction involves production of Characteristic X-Rays?

Answer 52

ionization

Question 53

Which interaction involves production of infrared photons?

Answer 53

Excitation

Question 54

Which of the following, if it is the only thing changed, will increase noise on the digital image?

Answer 54

a. Increased source to image distance b. Reduction of kVp c. I ncrease in filtration 2 d. Reduction of mAs (e. All of the above)

Question 55

Which of the following is a compensating filter?

Answer 55

a. trough b. wedge X c.bow tie d.boomerang (e. All of the above)

Question 56

Which of the following transition results in the highest energy characteristic X-Ray?

Answer 56

O to K

Question 57

X-Ray intensity can be changed by changing

Answer 57

a. distance X F Flag question b. filtration C. kVp d. mAs (e. All of the above)

Question 58

X-Ray quality is measured in

Answer 58

half-value layers (HVL)

Question 59

X-Ray quantity is_____ filtration.

Answer 59

exponentially related to

Question 60

X-Ray quantity is measured in

Answer 60

Roentgens (R)