Deck 34: Exposure Conversion Problems

Question 1

A radiographer has received a request for an examination that requires a 12:1 grid based upon patient thickness.The exposure technique chart suggests a non-grid technique of 6 mAs at 90 kVp.The required mAs with the grid will be

A)12 mAs.
B)18 mAs.
C)30 mAs.
D)43 mAs.

Answer 1

30 mAs.

Question 2

The relationship between receptor speed and exposure mAs is

A)inverse.
B)indirect and linear.
C)direct.
D)direct and linear.

Answer 2

indirect and linear.

Question 3

Match the following choices with the statements as each relates to exposure conversions.
exposure maintenance formula

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Answer 3

density-distance relationship

Question 4

Match the following choices with the statements as each relates to exposure conversions.
Any change will not affect density or contrast.

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 5

A particular radiograph was produced using 8 mAs and 84 kVp with an 8:1 ratio grid. The film is to be repeated using a 16:1 ratio grid. What should be the new mAs?

A)5 mAs
B)8 mAs
C)14 mAs
D)20 mAs

Question 6

Match the following choices with the statements as each relates to exposure conversions.
switch from 400 RS to 300RS with no compensation

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 7

A satisfactory radiograph is produced using the variable kVp theory.The part measuring 8 cm and 55 kVp was used.To maintain exposure, what kVp should be used if the part measures 10 cm?

Question 8

A satisfactory radiograph is produced using the variable kVp theory.The part measuring 10 cm and 65 kVp was used.To maintain exposure, what kVp should be used if the part measures 14 cm?

Question 9

An acceptable radiographic image is taken under the following conditions: single phase-2p, 400 mA, 75 ms, 1.2 mm fs, 82 kVp, 44" SID, 400 RS receptor, 8:1 grid.
What change would need to take place with the exposure conditions below, in order to maintain image quality?
HF generator, 1.0 mm fs, 94 kVp, 44" SID, 300 RS receptor, 12:1 grid

A)Change the exposure to 300 mA , 46 ms.
B)Switch to a RS 200 receptor with no compensation.
C)Change to 20 mAs.
D)Decrease the SID to 40" with no compensation.

Question 10

A radiographic examination has been taken using the following exposure conditions: 400 mA, 70 ms, 80 kVp, 1,2 mm fs, 200 RS receptor, 12: grid, 44" SID
To increase the contrast, the most appropriate choice would be to

A)increase the mA to 500 and decrease time to 56 ms.
B)switch to the 0.8 mm focal spot.
C)switch to a 400 RS receptor and decrease the mAs.
D)switch to a 16:1 grid and increase mAs.

Question 11

Which of the following exposure settings will yield an image with the shortest scale of contrast?

A)200 mA, 0.09 s, 100 kVp, 12:1 grid
B)400 mA, 0.05 s, 75 kVp, 8:1 grid
C)300 mA, 0.06 s, 90 kVp, 10:1 grid
D)500 mA, 46 ms, 77 kVp 12:1 grid

Question 12

For a 20 cm part thickness, which of the following would accommodate a 6 cm increase in part thickness and maintain radiographic density?

A)Increase the kVp by 12 kVp.
B)Increase the mAs by 100%.
C)Increase the kVp by 20%.
D)either a or b

Question 13

An exposure was made using 200 mA, 0.05 second exposure and 75 kVp.Each of the following changes will function to double radiographic image density, EXCEPT:

A)Change to 0.1 sec exposure.
B)Change to 86 kVp.
C)Change to 20 mAs.
D)Change to 100 mA.

Question 14

Match the following choices with the statements as each relates to exposure conversions.
5 cm increase in tissue thickness

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 15

Match the following choices with the statements as each relates to exposure conversions.
affects radiographic contrast with a direct relationship

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 16

Match the following choices with the statements as each relates to exposure conversions.
reduce kVp from 94 to 84 with mAs compensation

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 17

Match the following choices with the statements as each relates to exposure conversions.
change from 12:1 to 10:1 with mAs compensation

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 18

When switching from an 8:1 grid to a 12: grid at 85 kVp, the change in mAs will be

A)decreased by 15%.
B)increased by 40%.
C)increased by 25%.
D)decreased by 40 %.

Question 19

Match the following choices with the statements as each relates to exposure conversions.
requires less mAs but does not affect recorded detail or distortion

A)decreased density
B)focal spot size
C)longer scale of contrast
D)grid ratio
E)receptor speed
F)increased mAs by 2x
G)additive pathology
H)higher amount of contrast
I)destructive pathology
J)density-distance relationship

Question 20

You are asked to fill in for a technologist at a local clinic for the day.When you arrive, you notice the x-ray generator is single phase.Your experience with exposure techniques was based upon a high frequency unit at the local hospital.To work at this clinic, you will likely do what to your hospital exposure techniques?

A)increase the kVp values by 15%
B)increase the mAs values by 100%
C)decrease the kVp values by 15% and double the mAs values
D)decrease the mAs values by 15%

Question 21

A radiograph is produced at 10 mAs with a single-phase, 2-pulse generator.The film is repeated using a high frequency generator with a three-phase source of power..Calculate the new mAs.

Question 22

A radiograph is produced at 10 mAs with a high frequency generator.The film is repeated using a single-phase, 2-pulse generator.Calculate the new mAs.

Question 23

A radiograph is produced using 15 mAs and an image receptor with an RS of 200.Calculate the new mAs if an image receptor of 400 RS is used.

Question 24

A radiograph is produced using 70 kVp and 10 mAs.If kVp is increased to 80, how much mAs is required to maintain exposure?

Question 25

A radiograph is produced using 70 kVp and 10 mAs.If mAs is decreased to 5, how much kVp is required to maintain exposure?

Question 26

A satisfactory radiograph is produced as follows: 1 $\phi$ 2p, 70 kVp, 30 mAs, 40 in.SID, 8:1 grid, 200 RS.A new radiograph is to be produced with the following changes: high frequency, 12:1 grid, and 400 RS.What changes should be made to maintain the original exposure?

Question 27

A radiograph is produced using 10 mAs at a 40 in.distance.Calculate the new mAs at a 72 in.distance.

Question 28

A radiograph is produced using 70 kVp and 10 mAs.If kVp is decreased to 60, how much mAs is required to maintain exposure?

Question 29

A radiograph is produced at 10 mAs with a single-phase, 2-pulse generator.The film is repeated using a high frequency generator.Calculate the new mAs.

Question 30

A radiograph is produced at 10 mAs with a single-phase, 2-pulse generator.The film is repeated using a three-phase, high frequency generator.Calculate the new mAs.

Question 31

A satisfactory radiograph is produced using the fixed kVp theory.The part measuring 10 cm and 8 mAs was used.To maintain exposure, what mAs should be used if the part measures 14 cm?

Question 32

A radiograph is produced using 10 mAs at a 40 in.distance.Calculate the new distance if 25 mAs is used.

Question 33

A radiograph is produced at 10 mAs with a single-phase power source and high frequency generator.The film is repeated using a single-phase, 2-pulse generator.Calculate the new mAs.

Question 34

A radiograph is produced using 20 mAs, 85 kVp, and an 8:1 grid (GCF = 4).Calculate the new mAs if a 12:1 grid (GCF = 5.5) is used.

Question 35

A satisfactory radiograph is produced using the fixed kVp theory.The part measuring 10 cm and 6 mAs was used.To maintain exposure, what mAs should be used if the part measures 6 cm?

Question 36

A radiograph is produced at 10 mAs with a three-phase, high frequency generator.The film is repeated using a single phase,2-pulse generator.Calculate the new mAs.

Question 37

A radiograph is produced using 10 mAs and an image receptor with an RS of 200.Determine the relative speed of the new image receptor if 5 mAs is used.

Question 38

A radiograph is produced using 70 kVp and 10 mAs.If mAs is increased to 20, how much kVp is required to maintain exposure?