RADT_153_Unit_5_Exam - RADT 153 Image Analysis Unit 5 The...

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Unformatted text preview: RADT 153 Image Analysis Unit 5 The Effects of Milliampere-Seconds on Radiographic Quality Unit Exam 2 5.0 The Effects of Milliampere-Seconds on Radiographic Quality Directions: 1. Write your name and the date on your Scantron form. Identify the subject as the course number (for example, RADT 153) along with the test number (for example, Unit 4). 2. For each of the questions below, select the best answer to the question. 3. Using a No. 2 pencil, fill in the appropriate answer on the answer sheet. 4. Erase unwanted answers completely. Questions with two or more filled in answer spaces are graded as incorrect. 5. Answer all questions. 6. You have a maximum 15 minutes to complete the following 25 questions. (Note: This time factor approximates the amount of time you would be allowed to answer the same number of questions on the Registry examination in radiography). 1. mA is equal to _________________________. A. B. C. D. E. 2. one-thousandth of an ampere one-hundredth of an ampere one-tenth of an ampere one ampere one one-hundredth of an ampere Which of the following is not needed to produce x-rays? A. B. C. D. acceleration of electrons source of electrons strong magnetic field stoppage of electrons 3 3. Electrons are controlled by the __________________________. A. B. C. D. E. 4. Where do the electrons come from? A. B. C. D. E. 5. True False The relationship between mA, electron production and radiation output is direct. A. B. 8. thermionic emission temperature regulation rectification none of the above The hotter the filament becomes the lesser the number of electrons boiled off. A. B. 7. Copper filament wire Tungsten filament wire Aluminum filament All of the above Only A and B The process of electrons being boiled off the filament wire is called ________________________. A. B. C. D. 6. focal sport cathode current through the filament wire anode saturation current True False When the mA is increased the electrons produced _____________. A. B. C. D. E. decreases increases are not effected separate none of the above 4 9. Controlling the number of electrons will determine the amount of ___________ in the primary beam. A. B. C. D. E. 10. mA controls ____________________. A. B. C. D. E. 11. True False If an exposure does not have a sufficient density but the part is sufficiently penetrated, then ______________ should be increased. A. B. C. D. E. 14. mA kVp time OID part thickness The radiographer must be careful when changing the exposure time because and increase in the time will increase the opportunity for movement and loss of recorded detail. A. B. 13. contrast recorded detail fogging density all of the above What controls the length of the x-ray exposure? A. B. C. D. E. 12. radiation x-rays cosmic rays scatter absorption mAs kVp time distance filtration If a technique requires 20 mAs and the control panel has a 200 mA station what is the shortest exposure time that can be used? 5 A. B. C. D. E. 15. If an imager is operated at 600mA, 50 ms, the total mAs will be which of the following? A. B. C. D. E. 16. E. proper set up insertion of information cover unknown information take the two remaining factors and multiply or divide as needed all of the above When using the memory wheel; two numbers are side by side the numbers should be ____________. When the one number lies on top and one number is on the bottom; the numbers should be ______________. A. B. C. D. E. 18. 6 30 60 300 600 Which of the following are steps to using the memory wheel? A. B. C. D. 17. 1/10 second 1 min. 1 second 1/5 second 1/25 second Added, Subtracted Subtracted, Added Added, Multiplied Divided, Multiplied Multiplied, Divided What does increasing mA do? A. B. C. D. E. controls current flow through the x-ray circuit controls current flow to the filament controls potential difference between cathode and anode regulates radiation output Only A and D 6 19. kVp controls penetration and thermionic emission. A. B. 20. ___________ is directly proportional to mAs. A. B. C. D. E. 21. contrast density kVp mAs keV When an optimum (best) kVp is used, a change in mAs will ____________ the contrast of the radiographic image. A. B. C. D. E. 24. .5% 5% 10% 25% 50% ___________ is the measurable or observed difference between adjacent radiographic densities. A. B. C. D. E. 23. magnification definition contrast density foreshortening If the mAs is changed 10%, the amount of density on the radiograph will change by approximately ____%. A. B. C. D. E. 22. True False increase decrease obscure not affect non of the above Too much mAs can render recorded detail useless. A. B. True False 7 25. The “bloom effect” is cause by: A. B. C. D. E. high kVp, high mAs high kVp, low mAs low kVp, high mAs low kVp, low mAs movement ...
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This note was uploaded on 11/12/2011 for the course RADIOLOGY 153 taught by Professor Walters during the Spring '11 term at Boise State.

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