Ch. 11 (Exp I)

Question 1

The factors that affect x-ray emission under the direct control of the radiographer are called the _____ factors.

Answer 1

Prime

Question 2

The prime factors include all of the following except:

a. filtration
b. mAs
c. kVp
d. distance

Answer 2

a. filtration

Question 3

Milliamperage-second (mAs) directly affects all of the following except:

a. beam quantity
b. beam intensity
c. beam quality
d. x-ray output

Answer 3

c. beam quality

Question 4

The factors that directly affect x-ray quantity are:

Answer 4

mA and time

Question 5

X-ray beam quality is numerically represented by the:

Answer 5

HVL

Question 6

The factors that directly affect x-ray quality are:

Answer 6

kVp and beam filtration

Question 7

If 1 coulomb is equal to 6.3 x 10^18 electron charges, how many electrons flow from cathode to anode in 1 second?

Answer 7

6.3 x 10^18

Question 8

If 1 ampere equals a flow of 6.3 x 10^18 electrons per second, how many electrons flow from cathode to anode in 1 milliampere?

Answer 8

6.3 x 10^15

Question 9

As the mA doubles, the number of electrons flowing from cathode to anode…

Answer 9

Increases twofold

Question 10

The product of the tube current and exposure time is equal to:

Answer 10

x-ray beam quantity

Question 11

The primary factor controlling x-ray beam quantity is determined by:

Answer 11

mAs

Question 12

In order to increase radiographic film density by 40%, the radiographer would:

a. Change the mAs from 15 to 21 mAs
b. decrease the kVp by 40%
c. Increase the mAs by 20%
d. Decrease the distance by 40%

Answer 12

a. Change the mAs from 15 to 21 mAs

Question 13

If the mAs of a radiograph is increased from 10 to 20, the resulting radiograph will exhibit:

Answer 13

Increased radiographic film density

Question 14

The relationship between mAs and exposure is:

Answer 14

Directly proportional

Question 15

The reaction of a photographic film to light is equal to the product of the intensity of the light and the duration of the light exposure. This concept is known as:

Answer 15

The reciprocity law

Question 16

Increasing the energy of an incident electron will result in the production of an x-ray photon with:

Answer 16

Greater energy

Question 17

If kVp is doubled, the amount of x-ray photons created approximately increases:

Answer 17

Fourfold

Question 18

Kilovoltage is the primary controlling factor of:

Answer 18

Radiographic film contrast

Question 19

An increase in kVp by 15 percent will cause an approximate _____ in the exposure.

Answer 19

Doubling

Question 20

Adjustments in kVp should be used to control radiographic _______.

Answer 20

Contrast

Question 21

X-ray beam penetrability is primarily controlled by _____.

Answer 21

kVp

Question 22

The relationship between the intensity of radiation and distance is the…

Answer 22

Inverse square law

Question 23

The density maintenance formula is a…

Answer 23

Direct square law

Question 24

All factors remaining contrast, which of the following set of exposure conditions would yield an image with the greatest radiographic film density?

a. 100 mA, 0.75 sec, 40” SID
b. 300 mA, 0.25 sec, 44” SID
c. 600 mA, 125 ms, 40” SID
d. 400 mA, 200 ms, 40” SID

Answer 24

d. 400 mA, 200 ms, 40” SID

- Has highest mAs of 80 (all others at 75 mAs)

Question 25

All factors remaining constant, which of the following set of exposure conditions would yield an image with the greatest radiographic film density?

a. 100 mA, 0.75 sec, 40” SID, 70 kVp
b. 150 mA, 0.25 sec, 44” SID, 80 kVp
c. 300 mA, 125 ms, 40” SID, 70 kVp
d. 400 mA, 187 ms, 56” SID, 88 kVp

Answer 25

d. 400 mA, 187 ms, 56” SID, 88 kVp

- Options a and d have 75 mAs (b and c have 37.5 mAs). d has a higher kVp than option a giving it more density than a.

Question 26

After completing an upright abdomen radiograph using A.E.C., you notice some degree of motion artifact on the final image. To improve the repeat image results, your best option would be to:

a. Decrease the kVp
b. Increase your distance
c. Double the mA and decrease the kVp by 15%
d. Increase the kVp by 15%

Answer 26

d. Increase the kVp by 15%

Question 27

Which of the following sets of exposure factors would best control involuntary motion?

a. 100 mA, 0.09 sec
b. 300 mA, 30 ms
c. 500 mA, 18 ms
d. 200 mA, 0.045 sec

Answer 27

c. 500 mA, 18 ms

- Has the shortest time.

Question 28

The length of the exposure time (s) for a radiograph, is used to primarily control:

Answer 28

Motion

Question 29

A radiograph is taken at 400 mA, 55 ms, 95 kVp. A second image could be taken to improve contrast at:

Answer 29

400 mA, 0.110 sec, 80 kVp.

-Double the mA, reduce kVp by 15%