Introduction To Health Physics
5th Edition
ISBN: 9780071835275
Author: Johnson, Thomas E. (thomas Edward), Cember, Herman.
Publisher: Mcgraw-hill Education,
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 6, Problem 6.8P
(a)
To determine
The photon flux.
(b)
To determine
The power density
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Typical 10-fold intensity reduction values for X-ray radiation with energy 1 MeV are 30 cm for bone tissues, 20 cm for aluminum, 5 cm for lead. Find mass and linear attenuation coefficients if densities are 1.85 g/cm3, 2.70 g/cm3, 11.35 g/cm3, respectively.
Typical HVL values for X-ray radiation with energy 1 MeV are 3 cm for bone tissues, 2 cm for aluminum,
0.3 cm for lead. Find mass and linear attenuation coefficients if densities are 1.85 g/cm3 , 2.70 g/cm3 , 11.35 g/cm3, respectively.
A photon has an energy of 1.9 meV (milli electron Volt). What is the wavelength of this photon, expressed in micrometers? Keep four significant digits.
And the answer is NOT 6.543
Chapter 6 Solutions
Introduction To Health Physics
Ch. 6 - A 50-µC/kg (approximately 200 mR) pocket dosimeter...Ch. 6 - Prob. 6.2PCh. 6 - Prob. 6.3PCh. 6 - Prob. 6.4PCh. 6 - Prob. 6.5PCh. 6 - Prob. 6.6PCh. 6 - Prob. 6.7PCh. 6 - Prob. 6.8PCh. 6 - Prob. 6.9PCh. 6 - Prob. 6.10P
Ch. 6 - Prob. 6.11PCh. 6 - Prob. 6.12PCh. 6 - Prob. 6.13PCh. 6 - Prob. 6.14PCh. 6 - Prob. 6.15PCh. 6 - Prob. 6.16PCh. 6 - Prob. 6.17PCh. 6 - Prob. 6.19PCh. 6 - Prob. 6.20PCh. 6 - Calculate the average power density, in watts per...Ch. 6 - Prob. 6.22PCh. 6 - Prob. 6.23PCh. 6 - Prob. 6.24PCh. 6 - Prob. 6.26PCh. 6 - Prob. 6.27PCh. 6 - Prob. 6.28PCh. 6 - Prob. 6.29PCh. 6 - Prob. 6.33P
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- 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?arrow_forward25. A radiograph made with an exposure of 12 mA per minute has a density of 0.8 in the area of interest. It is desired to increase the density to 2.0 in this area. By reference to a characteristic curve of the film, it is found that the difference in log e between a density of 0.8 and 2.0 is 0.76. The antilogarithm of log 0.76 is 5.8 (relative exposure factor). What must the new exposure time be to produce a radiograph with a density of 2.0, assuming the first exposure time was 1 minute?arrow_forwardThe linear absorption coefficient of 1 MeV X-rays in water is 7.06 m-1. How many times will the radiation intensity decrease in a 19.6 cm thick water layer?arrow_forward
- Gamma-ray detectors like the one described in the preceding problem often use calorimetry to determine gamma-ray energies. Suppose a beam of 100-MeV gamma rays strikes a target with a mass of 2.5 kg and specifi c heat 430 J/(kg # K). How many gamma rays are needed to raise the target’s temperature by 10 mK?arrow_forwardA particular star has a radius of 8.46 ✕ 108 m. The peak intensity of the radiation it emits is at a wavelength of 679 nm. (a) What is the energy (in J) of a photon with this wavelength? answer in J (b) What is the star's surface temperature (in K)? (Round your answer to at least the nearest integer.) answer in K (c) At what rate (in W) is energy emitted from the star in the form of radiation? Assume the star is a blackbody, with emissivity e = 1. answer in W (d) Using the results from parts (a) and (c), estimate the rate (in photons/s) at which photons are emitted by the star. answer in photon/sarrow_forwardif a record sample has rate of 44100Hz, how many samples are required to capture 0.25s?arrow_forward
- Find required thickness of the protective lead shield in order to achieve 99 % reduction ofX-Ray radiation intensity. The mass attenuation coefficient for a radiation source with an energy of140 keV is μm = 2.32 cm2/g. Density of lead ρ = 11.35 g/cm3.arrow_forwardA Perspex (Lucite) phantom is used to calibrate a 6 MV photon beam. A cylindrical air ion chamber has a wall thickness (polystyrene) of 0.20 g/cm2 and an inner diameter of 5 mm. The ion chamber is placed at a depth of 5 cm in the phantom. The NxAion = 1.05 × 1010 R/C (T = 22 oC, P = 760 torr) for Co-60 for this chamber. Charge collected is 2.50 × 10-8C at P = 750 torr and T = 20.0 oC. The ion collection efficiency is 0.985. (a) Calculate the Ngas (Gy/C) for the chamber. (b) Calculate the absorbed dose (Gy) in Perspex at this depth. (c) What would be the absorbed dose (Gy) in water at approximately the same depth in a water phantom?arrow_forwardAt around 150keV, If you know that the mass attenuation coefficient of lead is around 4 cm2 /g, and that its density is 11.34 g/cm3 : a) What is the half-value layer (HVL) of lead at this photon energy? b) How many sheets of HVL thickness you need to use in order to attenuate the X-ray beam at around 150keV to be lower than 10-3 of its incident intensityarrow_forward
- Problem 1 Use the properties of Gamma functions to solve these expressions by hand. a program such as a T[ ] × [4] b C 3 — 92 xr 5 9 T[-2] × [2] Г xr 4 4arrow_forwardWhen photons pass through matter, the intensity I of the beam (measured in watts per square meter) decreases exponentially according to I = I0e-μxwhere I is the intensity of the beam that just passed through a thickness x of material and I0 is the intensity of the incident beam. The constant μ is known as the linear absorption coefficient, and its value depends on the absorbing material and the wavelength of the photon beam. This wavelength (or energy) dependence allows us to filter out unwanted wavelengths from a broad-spectrum x-ray beam.(a) Two x-ray beams of wavelengths λ1 and λ2 and equal incident intensities pass through the same metal plate. Show that the ratio of the emergent beam intensities is (I2)/(I1) = e-(μ2 - μ1)x(b) Compute the ratio of intensities emerging from an aluminum plate 1.00 mm thick if the incident beam contains equal intensities of 50 pm and 100 pm x-rays. The values of μ for…arrow_forwardThe mass attenuation coefficient of copper is 0.0589 cm2/g for 1.0-MeV photons. The intensity of 1.0MeV X-ray photons in a narrow beam is reduced to what fraction by a slab of copper 1 cm thick? The density of copper is 8.9 g/cm3.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning