Introduction To Health Physics
5th Edition
ISBN: 9780071835275
Author: Johnson, Thomas E. (thomas Edward), Cember, Herman.
Publisher: Mcgraw-hill Education,
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Chapter 9, Problem 9.21P
To determine
The gamma threshold energy.
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Problem 1
Use the properties of Gamma functions to solve these expressions by hand. a program such as
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xr
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4
a. A dental x-ray machine has a 60 kV accelerating voltage and a tungsten target. Atypical exposure uses an 8.0 mA electron current for 18 s. What is the approximatepower of the x-ray emission? The conversion efficiency is not known precisely, so aone-significant-figure answer is appropriate.
b. What is the x-ray intensity at the jaw, 15 cm from the source? Assume that the x raysare emitted uniformly in all directions from a single point.
c. A molar tooth can be approximated as a 9-mm-diameter, 20-mm-long cylinder. X raysimpinge on a molar from the side, perpendicular to the axis of the cylinder. Approxi-mately what x-ray energy enters a molar during the exposure?
The count rate for a particular a source X is C0 on a detector placed 1 m from the source. When a metal sheet of thickness 5mm is placed between source and counter the count rate drops by 75%.
What is the value of the attenuation coefficient, μ, for this radiation and metal?
Chapter 9 Solutions
Introduction To Health Physics
Ch. 9 - Prob. 9.1PCh. 9 - Prob. 9.2PCh. 9 - Prob. 9.3PCh. 9 - Prob. 9.4PCh. 9 - Prob. 9.5PCh. 9 - Prob. 9.6PCh. 9 - Prob. 9.7PCh. 9 - Prob. 9.8PCh. 9 - Prob. 9.9PCh. 9 - Prob. 9.10P
Ch. 9 - Prob. 9.11PCh. 9 - Prob. 9.12PCh. 9 - Prob. 9.13PCh. 9 - A counting system has a background of 360 counts...Ch. 9 - Prob. 9.15PCh. 9 - Prob. 9.16PCh. 9 - Prob. 9.17PCh. 9 - Prob. 9.18PCh. 9 - Prob. 9.19PCh. 9 - Prob. 9.20PCh. 9 - Prob. 9.21PCh. 9 - Prob. 9.22PCh. 9 - Prob. 9.23PCh. 9 - Prob. 9.24PCh. 9 - Prob. 9.25PCh. 9 - Prob. 9.26PCh. 9 - Prob. 9.27PCh. 9 - Prob. 9.28PCh. 9 - Prob. 9.29PCh. 9 - Prob. 9.31PCh. 9 - Prob. 9.33PCh. 9 - Prob. 9.34PCh. 9 - Prob. 9.35PCh. 9 - Prob. 9.38PCh. 9 - Prob. 9.39PCh. 9 - Prob. 9.44P
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