- #1
MixedWanton
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Questions, questions, questions... I hope some one can answer these questions. thank you. :)
1. Describe the process of Compton Scattering, explaining carefully how both attenuation and absorption of X-rays occur.
2. How does the process of Compton scattering of X-rays depend on the nature of the scattering material and upon X-ray energy? What is the significance of the process in radiographic imaging?
3. Explain why radiographic exposures are usually made with an X-ray tube voltage in the range 50-110kVp.
4. A parallel beam of monoenergetic X-rays impinges on a piece of lead. What is the origin of any lower energy X-rays which emerge from the other side of the sheet traveling in the same direction as the incident beam?
5. How would a narrow beam, of 100kV X-rays be changed as it passed through a thin layer of material? What differences would there be if the layer were (a) 1 mm lead (Z = 82, ρ = 1.1 x 104 kg m-3), (b) 1mm aluminum (Z = 13, ρ = 2.7 x 103 kg m-3)?
6. What factors determine whether a particular material is suitable as a filter for diagnostic radiology?
7. Discuss the advantages and disadvantages of using aluminum as a filter material in X-ray sets at different generating potentials.
8. The dose rate in air at a point in a narrow beam of X-rays is 0.3 Gy min-1. Estimate, to the nearest whole number, how many half-value thickness of lead are required to reduce the dose rate to 10-6 Gy min-1 Gy min-1. If H1/2 at this energy is 0.2mm, what is the required thickness of lead?
9. Explain what you understand by the homogeneity of an X-ray beam and describe briefly how you would measure it.
1. Describe the process of Compton Scattering, explaining carefully how both attenuation and absorption of X-rays occur.
2. How does the process of Compton scattering of X-rays depend on the nature of the scattering material and upon X-ray energy? What is the significance of the process in radiographic imaging?
3. Explain why radiographic exposures are usually made with an X-ray tube voltage in the range 50-110kVp.
4. A parallel beam of monoenergetic X-rays impinges on a piece of lead. What is the origin of any lower energy X-rays which emerge from the other side of the sheet traveling in the same direction as the incident beam?
5. How would a narrow beam, of 100kV X-rays be changed as it passed through a thin layer of material? What differences would there be if the layer were (a) 1 mm lead (Z = 82, ρ = 1.1 x 104 kg m-3), (b) 1mm aluminum (Z = 13, ρ = 2.7 x 103 kg m-3)?
6. What factors determine whether a particular material is suitable as a filter for diagnostic radiology?
7. Discuss the advantages and disadvantages of using aluminum as a filter material in X-ray sets at different generating potentials.
8. The dose rate in air at a point in a narrow beam of X-rays is 0.3 Gy min-1. Estimate, to the nearest whole number, how many half-value thickness of lead are required to reduce the dose rate to 10-6 Gy min-1 Gy min-1. If H1/2 at this energy is 0.2mm, what is the required thickness of lead?
9. Explain what you understand by the homogeneity of an X-ray beam and describe briefly how you would measure it.