Practice Problems & Ch.34 Flashcards
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 %
Increased by 40%
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.
30 mAs
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
500 mA, 46 ms, 77 kVp, 12:1 grid
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%
increase the mAs values by 100%
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.
Switch to a 16:1 grid and increase mAs
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.
Change to 100 mA
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
14 mAs
The relationship between receptor speed and exposure mAs is
a. inverse
b. indirect and linear
c. direct
d. direct and linear
Indirect and linear
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.
Change the exposure to 300 mA, 46 ms
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
Either a or b
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?
73 kVp
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?
59 kVp
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?
16 mAs
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?
3 mAs
A radiograph is produced using 70 kVp and 10 mAs. If kVp is increased to 80, how much mAs is required to maintain exposure?
5 mAs