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RA 202 Physics Class 1 Multiple Choice Identify the Letter of the Choice That Best Completes the Statement Or Answers the Questi

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RA 202 Physics Class 1 Multiple Choice Identify the Letter of the Choice That Best Completes the Statement Or Answers the Questi RA 202 Physics Class 1 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. ____ 1. What is the source of x-ray photons in the tube? a. cathode c. rotor b. filament d. anode ____ 2. Which of the following occur as a result of filtration? 1. increase quality of the beam 2. harden the beam 3. eliminate high-energy x-ray photons a. 1 and 2 c. 1 and 3 b. 2 and 3 d. 1, 2, and 3 ____ 3. The primary purpose of the focusing cup is to a. narrow the electron cloud before c. rotate the anode by utilizing an acceleration towards the target induction motor b. house the anode d. transform electrons to x-ray photons ____ 4. What will happen when the technologist fails to select the proper bucky during an exposure? a. exposure will terminate when c. film will be overexposed backup time has been reached b. increased exposure to the patient d. all of these ____ 5. Which type of x-ray photon is produced when the incident electron passes close to the nucleus of the target material, altering its course? a. braking photons c. characteristic photons b. k-rays d. free radicals ____ 6. What type of transformer is utilized in the filament circuit? a. autotransformer c. step-down transformer b. step-up transformer d. all of these ____ 7. A single phase generator with full-wave rectification will utilize ___ pulses per cycle. a. 1 c. 3 b. 2 d. 6 ____ 8. An electron is accelerating toward the anode from the thermionically emitted cloud is referred to as a/an a. incident electron c. secondary electron b. incident photon d. secondary photon ____ 9. A low-energy x-ray photon is said to have a ____ frequency and a ____ wavelength. a. high, short c. low, short b. high, long d. low, long ____ 10. The capability of mA and kV adjustment to occur during fluoroscopy when moving the tube across different anatomical regions is accomplished by a. the auto transformer c. the automatic exposure control b. the automatic brightness control d. the ionization chamber ____ 11. Which type of AEC employs a photo-sensitive screen on the opposite side of the cassette from the tube? a. backup timer c. phototimer b. photomultiplier d. ionization chamber ____ 12. What material makes up the target for mammographic units? a. tungsten c. copper b. molybdenum d. nickel ____ 13. Another name for coherent scatter is a. classical scatter c. modified scatter b. characteristic scatter d. compton scatter ____ 14. On a diagram of the basic x-ray circuit, where would the rectification system be located? a. on the primary side of the main x- c. on the primary side of the filament ray circuit circuit b. on the secondary side of the main d. on the secondary side of the x-ray circuit filament circuit ____ 15. The cathode end of the x-ray tube possesses a ________ charge. a. positive c. neutral b. negative ____ 16. In the fluoroscopic tube, electrons are focused and accelerated toward the image intensifier by a. the photocathode c. electrostatic lenses b. the input phosphor d. the output phosphor ____ 17. A device that converts mechanical energy to electrical energy is called a/an a. generator c. induction motor b. motor d. transformer ____ 18. How could you double the number of incident electrons produced? 1. double your mA 2. double your time 3. increase your kVp by 15% a. 1 and 2 c. 2 and 3 b. 1 and 3 d. 1, 2, and 3 ____ 19. What type of beam restriction device is referred to as a “variable aperture diaphragm?” a. cone c. collimator b. cylinder d. none of these ____ 20. The process of boiling off electrons at the filament is called a. space charge effect c. thermal conductivity b. thermionic emission d. ionization ____ 21. Why is a rotating anode more desirable than a stationary anode in general radiography rooms? a. increases recorded detail c. allows for greater range of SID usage b. higher efficiency for heat d. none of these dissipation ____ 22. What must happen to change a primary x-ray photon to a secondary x-ray photon? a. it must leave the glass envelope c. it must reach the anode b. it must decelerate and change d. it must be absorbed in the patient course ____ 23. Acceleration of electrons occurs when _____ is applied to the filament. a. Watts c. milli-amperage b. Joules d. kilovoltage ____ 24. What is the primary purpose of the glass housing? a. protect the anode assembly c. protect the cathode assembly b. provide a vacuum d. provide protection from radiation leakage ____ 25. A 3 phase, 12 pulse generator utilizes ___ pulses per second. a. 6 c. 360 b. 12 d. 720 ____ 26. If you suspect a lateral c-spine could be taken using 30 mAs, but wish to use AEC for the exposure, what should you set the backup mAs to be? a. 35mAs c. 45mAs b. 40mAs d. 60mAs ____ 27. Attenuation of the x-ray beam _____ as atomic number of the part being radiographed increases. a. increases c. remains the same b. decreases ____ 28. What type of target interaction results from the incident electron ejecting an inner-shell Tungsten target electron? a. Bremsstrahlung interaction c. photoelectric effect b. braking radiation d. characteristic interaction ____ 29. The majority of the useful x-ray beam is composed of mainly a. secondary radiation c. k-rays b. Brem’s rays d. characteristic rays ____ 30. What type of charge does the anode have? a. positive c. neutral b. negative RA 202 Physics Class 1 Answer Section MULTIPLE CHOICE 1. ANS: D 2. ANS: A 3. ANS: A 4. ANS: D 5. ANS: A 6. ANS: C 7. ANS: B 8. ANS: A 9. ANS: D 10. ANS: B 11. ANS: C 12. ANS: B 13. ANS: A 14. ANS: B 15. ANS: B 16. ANS: C 17. ANS: A 18. ANS: A 19. ANS: C 20. ANS: B 21. ANS: B 22. ANS: B 23. ANS: D 24. ANS: B 25. ANS: D 26. ANS: C 27. ANS: A 28. ANS: D 29. ANS: B 30. ANS: A .
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