Download rad1exam1su99

DISCLAIMER: Please be advised that the information contained within this text is extra study material and should NOT be
deemed as completely correct without mistakes. It is the responsibility of the user to verify the correctness of ALL information
contained within.
Rad1 Physics
Exam 1
Summer 1999
1.
T or F: Electrons give off energy when they move to a lower energy shell.
2.
T or F: Absorption of energy occurs when electrons move to a higher shell, which is called excitation.
3.
T or F: Roentgen’s velocity theory states that photons are created at a constant velocity or not at all.
4.
T or F: The velocity of all x-rays is 186,000 m/s.
5.
T or F: Einstein’s theory states that electromagnetic energy can behave as a particle or a wave.
6.
T or F: Bone appears white because it is radiopaque.
7.
T or F: X-rays travel at the speed of sound.
8.
T or F: X-rays produce scatter.
9.
T or F: X-rays ionize matter and cause certain crystals to fluoresce.
10. T or F: X-ray tube requires electricity to accelerate electrons from anode to cathode.
11. T or F: Single-phase machine has the most or highest ripple.
12. T or F: Low frequency machines generate almost pure DC current.
13. T or F: Regarding heel effect, a smaller anode angle will absorb less of the X-ray beam
14. T or F: Filtration is described by the thickness of aluminum
15. Wavelength is measured in:
a) hertz
b) angstroms
c) ohms
d) amps
e) watt
16. Property that is not associated with x-rays include:
a) highly penetrable
b) cannot be focused by a lens
c) interact with film efficiently
d) are invisible
17. X-rays travel in a straight line and diverge from their source. Which is not associated with this fact?
a) penumbra
b) magnification
c) distortion
d) beam convergence
e) inverse square law
18. Of the types of x-rays listed, which has the lowest energy?
a) Diffraction
b) Grenz
c) Orthovoltage
d) Diagnostic
1
DISCLAIMER: Please be advised that the information contained within this text is extra study material and should NOT be
deemed as completely correct without mistakes. It is the responsibility of the user to verify the correctness of ALL information
contained within.
19. In what energy range do diagnostic x-rays fall into?
a) below 10 keV
b) 10 to 30 keV
c) 30 to 150 keV
d) 200 to 300 keV
20. Which device uses ionization to measure x-ray intensity?
a) film badge
b) docimeter
c) geiger counter
d) all the above
21. Which substance is a good conductor?
a) copper wire
b) glass
c) rubber
d) a and b
22. The side of the tube that is positive or has a deficiency of electrons is the
a) cathode
b) anode
c) stator
23. Electrons are boiled off what part of the tube.
a) rotating anode
b) glass envelope
c) focusing cup
d) filament
24. What term describes the amount of current that flows through the filament?
a) watt
b) voltage
c) kVp
d) mAs
25. What term describes the potential or pressure that causes the electron to cross the gap in the tube?
a) watt
b) voltage
c) kVp
d) mAs
26. Which is not true concerning heat units.
a) is equal to kVp X mAs
b) limits how often machine may be used
c) varies from cathode to anode
d) varies from exposure to exposure
27. Which of the following changes alternating current to direct current?
a) transformer
b) generator
c) rectifier
d) motor
2
DISCLAIMER: Please be advised that the information contained within this text is extra study material and should NOT be
deemed as completely correct without mistakes. It is the responsibility of the user to verify the correctness of ALL information
contained within.
28. Which of the following relies on induction.
a) transformer
b) generator
c) rectifier
d) motor
29. Autotransformers will not
a) provide voltage for the filament circuit
b) provide DC current to the tube
c) provide a convenient location for the kVp meter
d) provide voltage for the high voltage circuit
30. What part of the tube focuses or aims the electron beam toward the target?
a) filament
b) focusing cup
c) anticathode
d) lens
31. What portion of the tube keeps scatter radiation from leaking out?
a) envelope
b) oil
c) casing
d) window
32. Which of the following is not an advantage of a rotating anode?
a) greater heat capacity
b) same area is not always bombarded with electrons
c) allows higher exposure at lower times
d) greater portability
33. Which timer utilizes an ion chamber for exposure control?
a) Mechanical
b) Synchronous
c) Electronic
d) AEC
34. You are testing the timer in a single-phase fully rectified machine in Toronto, Canada. Using the spin top test at
.05 seconds, how many dots should be seen?
a) 5
b) 6
c) 9
d) 12
35. Which timer is most often found in modern X-ray equipment?
a) Mechanical
b) Synchronous
c) Electronic
d) AEC
36. X-rays are made up of
a) Bremsstrahlung radiation
b) Characteristic radiation
c) A and B
d) None of the above
3
DISCLAIMER: Please be advised that the information contained within this text is extra study material and should NOT be
deemed as completely correct without mistakes. It is the responsibility of the user to verify the correctness of ALL information
contained within.
37. Which type of interaction is responsible for the heterogenesis of X-ray beams?
a) Bremsstrahlung
b) Characteristic
c) A and B
d) None of the above
38. A cloud of electrons gather around the filament, which gets large enough that the charge of this cloud, prevents
other electrons to be emitted from the filament. This is due to what effect?
a) edison effect
b) space charge effect
c) heel effect
d) compton effect
39. Uneven distribution of radiation from the cathode to the anode is due to what effect?
a) edison effect
b) space charge effect
c) heel effect
d) compton effect
40. Rebounding electrons from the focal point are referred to as
a) Bremsstrahlung radiation
b) Scatter radiation
c) Characteristic radiation
d) Off – focus radiation
41. Which is not used to help control the amount of heat generated at the anode?
a) use of low kVp and high mAs settings
b) use of tube rating chart
c) calculations of heat units
d) utilization of rotating anode
42. Oil surrounding the tube dissipates heat by which method?
a) evaporation
b) conduction
c) convection
d) oil is used for lubrication, not heat dissipation
43. “Spark over” type of tube failure is caused by which of the following?
a) evaporation of the filament
b) bearing failure
c) an exposure made that exceeds the rating of the tube
d) rapid increase in anode temperature
44. Which reaction creates characteristic radiation that is produced at the anode?
a) disintegration of nucleus
b) excitation
c) ionization
d) bremsstrahlung
45. Which interaction produces characteristic radiation?
a) bremsstrahlung
b) classic scatter
c) compton
d) photoelectric
4
DISCLAIMER: Please be advised that the information contained within this text is extra study material and should NOT be
deemed as completely correct without mistakes. It is the responsibility of the user to verify the correctness of ALL information
contained within.
46. Which interaction is a basis of subject matter?
a) bremsstrahlung
b) photoelectric
c) raleigh
d) thomson
47. Almost all scattering occurs during diagnostic range of
a) classic
b) compton
c) raleigh
d) thomson
48. What interaction has scatter radiation and recoil as its products?
a) compton
b) photoelectric
c) photo disintegration
d) pair production
49. Anti – matter is formed as a product of
a) compton
b) photoelectric
c) photo disintegration
d) pair production
50. A wedge filter is classified as which type of device
a) compensation filter
b) inherent filter
c) stereotactic filter
d) polarization filter
ANSWERS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
T
F
F
F
F
T
F
T
T
F
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
T
F
F
T
B
C
D
A
C
D
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
a
b
d
d
c
c
c
a
b
b
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
c
d
d
b
c
c
a
b
c
d
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
a
c
a
c
d
b
b
a
d
a
5