Final

Question 1

How does collimating to a smaller area effect contrast?

Answer 1

Contrast is increased

Question 2

Name two radiosensitive cells:

Answer 2

Lymphocyte and Sperm cells

Question 3

State two factors that increase the probability that a photon will undergo a photoelectric absorption interaction:

Answer 3

Low energy (kVP)
High atomic #

Question 4

Dosimeter reports express occupationally exposed persons doses in _____ units.

Answer 4

REM

Question 5

Increasing OFD _______ detail shapness.

Answer 5

Decreases

Question 6

When collimating from a 14x17 area to an 8x10 area you would ________ mAs

Answer 6

Increase by 50%

Question 7

Using oxidized developer ______ density and contrast.

Answer 7

Decreases

Question 8

State two condition for using a bucky grid:

Answer 8

• Part greater than 10 cm

- kVp greater than 60

Question 9

What is the purpose of using a bucky grid?

Answer 9

To reduce scatter radiation

Question 10

State one of the purposes of the fixer solution.

Answer 10

• To clear the unexposed silver halide crystals off the film.
• To harden the gelatin emulsion

Question 11

Where should a radiation dosimeter be worn?

Answer 11

On the collar, outside the apron.

Question 12

To maintain radiographic density: If the mAs is decreased by 50% the kVp should be:

Answer 12

Increased by 15%

Question 13

This technical factor controls the quantity of x-rays in the beam;

Answer 13

mAs (quantity/density)

Question 14

Name 3 radiation protection devices:

Answer 14

• Filter collimator
• Intensifying screen
• Lead shield
• Lead apron

Question 15

The developer solution converts silver halide to:

Answer 15

Black metallic silver

Question 16

Define linearity:

Answer 16

The ability to manipulate “mA x sec.” for the same radiographic density.

Question 17

State the charge that is on the focusing cup

Answer 17

Negative

Question 18

This type of ionizing radiation can be stopped by the outer layers of the skin:

Answer 18

Alpha particles

Question 19

State the two parts that make up the cathode:

Answer 19

• Focusing cup

- Filaments (long and short)

Question 20

X-rays are produced by ______ current.

Answer 20

Direct (DC)

Question 21

What does a rectifier do?

Answer 21

Converts AC to DC

Question 22

How often must lead walls be replace?

Answer 22

Never

Question 23

Assuming patient motion may be an issue, how should all mA and time setting be set?

Answer 23

Highest mA shortest exposure time

Question 24

Assuming all other factors are constant, as exposure time increases, image density ________.

Answer 24

Increases

Question 25

The ______ side of the image will exhibit the least radiographic density.

Answer 25

Anode

Question 26

As mAs increases, patient exposure _______.

Answer 26

Increases

Question 27

How do you select the small filament on the console?

Answer 27

Select one of the low mA settings.

- O our machines = 25, 72, or 150 mA

Question 28

Describe a a photon in terms of mass, charge, and velocity:

Answer 28

No mass
No charge
Speed of light

Question 29

What photographic property does mAs control?

Answer 29

Density

Question 30

The _______ controls the wavelength of the x-rays.

Answer 30

kVp

Question 31

Compare the wavelengths of x-rays produced to radiowaves:

Answer 31

X-ray wavelengths are shorter

Question 32

How must mAs be adjusted to double image density?

Answer 32

Double mAs

Question 33

mAs can be rounded ________ without a change in radiographic density.

Answer 33

30%

Question 34

State the formula for REM:

Answer 34

RAD x QF

Question 35

What is the relationship between x-ray frequency and wavelengths?

Answer 35

Inverse

Question 36

State the heat unit formula:

Answer 36

kVp x mAs

Question 37

Which x-ray production method is responsible for producing the majorit of the x-rays in the beam?

Answer 37

Bremstrahlung

Question 38

Optimum kVp for extremities under 10 cm is in the ______ range.

Answer 38

50-60 kVp

Question 39

This tpe of rectification produces the highest energy x-rays:

Answer 39

High frequency

Question 40

Describe the bremsstrahlung x-ray production process:

Answer 40

Electrons are decreased by the nuclear force field and changes directions. The charge in kinetic energy is converted to EM energy.

Question 41

State the optimum kVp range for spine imaging:

Answer 41

70-90

Question 42

Is optimum kVp higher for high frequency of full wave rectification?

Answer 42

Full wave

Question 43

Define ALARA:

Answer 43

Exposure as low as reasonably possible

Question 44

_____ mRAD = 1 RAD

Answer 44

1000

Question 45

Why does the path of film travel matter in automatic processing?

Answer 45

Chemical replenishment rates

Question 46

What is the only similarity between alpha particles, beta particles, and x-rays?

Answer 46

The can all ionize atoms

Question 47

____ characteristic x0rays of tungsten are useful.

Answer 47

K

Question 48

State the SI unit for REM

Answer 48

Seivert

Question 49

Where are compensating filters placed?

Answer 49

Between the collimator and the patient

Question 50

What is the #1 enemy of detail sharpness?

Answer 50

Motioin

Question 51

What is the purpose of using compensating filter?

Answer 51

To produce a uniform radiographic density.

Question 52

Why is the back of the cassette lined with lead?

Answer 52

To reduce backscatter radiation.

Question 53

The x-ray tube target is made of?

Answer 53

Tungsten

Question 54

Define radiographic density:

Answer 54

Blackness in the image

- Mass per unit volume of black metallic silver.

Question 55

Define ionize:

Answer 55

The total removal of an electron from its orbit.

Question 56

State the two AKA’s for SID:

Answer 56

TFD and FFD

Question 57

What are 2 of the 3 factors that influence comptons scatter production?

Answer 57

• kVp (energy)
• Collimated area
• Compression