| Question |
Answer |
| 1. What is the term for an energy form that travels the speed of light? |
photon |
| 2. How is Bremsstrahlung radiation produced? |
electron speeds close to the nucleus and high quality energy is released |
| 3. How is characteristic radiation produced? |
electron speeds close the inner orbit electrons and high quality energy is released |
| 4. What type of radiation is x-radiation? |
electromagnetic |
| 5. How fast does x-radiation travel? |
speed of light; 186,000 miles per second |
| 6. List the characteristics and properties of x-radiation. |
penetrate matter; produce a latent image; produce fluorescence;produce ionization; travel in straight lines; travel the speed of light; interact with electrons; interact with matter to produce scatter radiation |
| 7. What can be done to increase the amount of x-radiation emitted from the machine? |
increase the mA or the exposure time or both (mAs = mA x exp time in seconds |
| 8. What can be done to increase the quality of x-radiation emitted from the machine? |
increase kVp |
| 9. How will the radiograph be affected if the mA is decreased? |
lighter - lower in density |
| 10. How will the radiograph be affected if the kVp is increased? |
lower contrast (longer gray scale); darker - higher in density |
| 11. How will the radiograph be affected if the mA is increased? |
darker - higher in density |
| 12. How will the radiograph be affected if the kVp is decreased? |
higher contrast (shorter gray scale); lighter - lower in density |
| 13. What is the purpose of the focusing cup? |
direct the electrons towards the focal spot on the target during x-ray production |
| 14. Where do x-rays originate? |
the focal spot of the target on the anode side of the x-ray tube located in the tubehead |
| 15. What is the purpose of the filter? |
remove long wavelength x-rays of low penetrating ability |
| 16. What is the purpose for the collimator? |
control the size and shape of the x-ray beam |
| 17. What exposure setting determines the wavelength of the x-ray? |
kVp |
| 18. What quality of the x-ray is changed when the wavelength is changed? |
penetrating ability (wavelength) |
| 19. What type of collimator is recommended by the ADA? |
Rectangular |
| 20. What is stated by the inverse square law? |
intensity of the x-ray beam decreases inversely proportional to the square of the distance from the source (as the beam gets farther from the tube, it gets larger AND less concentrated) |
| 21. What is meant by short scale contrast? |
higher contrast radiograph with fewer shades of gray evident |
| 22. What is meant by long scale contrast? |
lower contrast radiograph with more shades of gray evident |
| 23. What exposure setting affects the contrast scale? |
kilovoltage - kVp |
| 24. What quality of the radiographic image will be affected by patient movement and film movement? |
sharpness aka definition |
| 25. What is the purpose for the filament? |
form electron cloud when machine is turned *on*, making available electrons for x-ray production |
| 26. What is the first thing that should be done if the x-ray machine malfunctions? |
turn it off |
| 27. How is the machine tested for tubehead drift? |
move the tubehead into various postions and see if it remains or drifts |
| 28. What is recommended if the tubehead drifts? |
have it repaired; in the meantime, do not use it |
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