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 5, Problem 5.37P
(a)
To determine
The microscopic cross- section for N and O for thermal neutrons.
(b)
To determine
The scattering means free path of thermal neutron.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A swimming pool reactor produces a flux of 3x1016 thermal neutrons m-2 s-1 at 1 m from the reactor center. Assuming a parallel beam of neutrons diffusing up to the surface of the pool where the neutron flux is measured to be 108 m -2 s-1. Calculate the thickness ( x m) of the water layer required. For thermal neutrons the flux is reduced exponentially with the experiment x L-1 where L is the diffusion length ( 2.75 cm in H2O).
Control rods are usually made of an alloy of indium. The absorption cross-section of indium for thermal neutron is 71 b, and the mass density of solid indium is 7.31 g cm-3. Estimate the neutron transmission ratio of a 1-cm thick indium slab.
(a) 0.07
(b)0.7
(c) 0.01
(d) 0.1
A point source of thermal neutrons is placed at the centre of a large sphere of
beryllium.
Deduce the spatial distribution of neutron density in the sphere. Estimate
what its radius must be if less than 1% of the neutrons are to escape through
the surface. Find also the neutron density near the surface in this case in terms
of the source strength.
At. Wt of beryllium = 9
Density of beryllium = 1.85 g/cc
Avagadro number = 6 x 1023 atoms/g atom
Thermal neutron scattering cross-section on beryllium = 5.6 barns
Thermal neutron capture cross-section on beryllium 10 mb (at velocity
v = 2,200 m/s)
=
Chapter 5 Solutions
Introduction To Health Physics
Ch. 5 - Prob. 5.1PCh. 5 - Prob. 5.2PCh. 5 - Prob. 5.3PCh. 5 - Prob. 5.4PCh. 5 - Prob. 5.5PCh. 5 - Prob. 5.6PCh. 5 - Prob. 5.7PCh. 5 - Prob. 5.8PCh. 5 - Prob. 5.9PCh. 5 - Prob. 5.10P
Ch. 5 - Prob. 5.11PCh. 5 - Prob. 5.12PCh. 5 - Prob. 5.13PCh. 5 - Prob. 5.14PCh. 5 - Prob. 5.15PCh. 5 - Prob. 5.16PCh. 5 - Prob. 5.17PCh. 5 - Prob. 5.18PCh. 5 - Prob. 5.19PCh. 5 - Prob. 5.20PCh. 5 - Calculate the probability that a 2-MeV photon in a...Ch. 5 - Prob. 5.22PCh. 5 - Prob. 5.23PCh. 5 - Prob. 5.24PCh. 5 - Prob. 5.25PCh. 5 - Prob. 5.26PCh. 5 - Prob. 5.27PCh. 5 - Prob. 5.28PCh. 5 - Prob. 5.29PCh. 5 - Prob. 5.30PCh. 5 - Prob. 5.31PCh. 5 - Prob. 5.32PCh. 5 - Prob. 5.33PCh. 5 - Prob. 5.34PCh. 5 - Prob. 5.35PCh. 5 - Prob. 5.36PCh. 5 - Prob. 5.37PCh. 5 - Prob. 5.38PCh. 5 - Prob. 5.39PCh. 5 - Prob. 5.40PCh. 5 - A 1-M solution of boric acid, H3BO3 , is...Ch. 5 - Prob. 5.42PCh. 5 - Prob. 5.43PCh. 5 - Prob. 5.44PCh. 5 - Prob. 5.45PCh. 5 - Prob. 5.46PCh. 5 - Prob. 5.47PCh. 5 - Prob. 5.49PCh. 5 - Prob. 5.50PCh. 5 - Prob. 5.54PCh. 5 - What is the range in tissue of the beta particles...Ch. 5 - Prob. 5.56P
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 certain medium has the following properties: Σs = 0.1 cm−1,Σa = 0.01 cm−1. a) What is the probability that a neutron will travel 1 cm in this medium without interacting with a nucleus? b) If the neutron speed is 2 ×105 cm s−1, what is the average time between scattering collisions?arrow_forwardThe cross section for neutrons of energy 10 eV being captured by silver (p = 10.5 g/cm3) is 17 barns. What is the probability of a neutron being captured as it passes through a layer of silver 2 mm thick?arrow_forwardConsider the region close to a nuclear reactor that produces large fluxes of prompt gamma rays with energies of about 7 MeV. Use the graph below, showing the mass attenuation coefficient of gamma rays in different stopping media as a function of energy, to determine the approximate thickness of lead shielding which would be required to reduce the gamma flux by a factor of 101º. The density of lead is 11.3 g cm. 10 5 Pb 0.5 0.1 Pb 0.05 Cu AL 0.01 0.01 0.05 0.1 0.5 1 5 10 50 100 Energy (MeV) Attenuation coefficient (cm²g")arrow_forward
- Let the total number of neutrons be Nn, the number of protons be Np, and N = Nn + Np. Let the fractions be Xi = Ni/N. (a) If the probability of a particle having energy E is proportional to the Boltzmann factor, exp(-E/kT), show that Xn/Xp exp(-1.3 MeV/kT). (b) For what temperature was the ratio of protons to neutrons in the universe 6.7? (c) What is the kinetic energy associated with this temperature? Is there anything noteworthy about this temperature?arrow_forwardA small 10-gram source of cobalt-60 is in a vacuum. (a) What is the activity of the cobalt-60source in Bq? (b) What is the actual gamma-ray flux in cm2-s-1 at a point of measurement500 cm from the source due to the cobalt-60 emitted gamma-rays? (c) If the backgroundgamma-ray flux in the vicinity of the 10-g source is 7.8×107cm-2-s-1, what is the totalgamma-ray flux at the point of measurement, including the background? (d) What thicknessof a lead shield in cm would have to be placed between the source and the point ofmeasurement to reduce the total of the background plus the uncollided gamma-ray flux fromthe cobalt-60 source to 1.00×108cm-2-s-1 at that point? (I've attempted part a of the problem and don't know how to continue)arrow_forwardPlease solve in 30 minutearrow_forward
- Problem 1. UA13 is used as a fuel in research nuclear reactor. Uranium-235 enrichment is 20%. Density of UAI3 is 6.8 g/cm. a) Calculate thermal neutron reproduction factor n for this fuel. b) What is the thermal power density in this fuel at a point where the thermal neutrons flux is 1.09x1013 n/cm²s? c) Determine power of the reactor if the mass of fuel is 75 kg and average flux is 1.0×101³ n/cm³s. Assume that average energy released per fission reaction is 200 MeV.arrow_forward(a) Calculate the mass and linear absorption coefficients of air for Cr Ka radiation.Assume that air contains 80 percent nitrogen and 20 percent oxygen by weight and has adensity of1.29 x g/cm3. (b) Plot the transmission factor of air for Cr Ka radiationand a path length of 0 to 20 cm.arrow_forwardCalculate the prompt temperature coefficient of reactivity at temperature 25° C of a reactor lattice consisting of an assembly of natural uranium (metallic) rods with a diameter of 3.3 cm in a heavy water moderator, in which the moderator volume to fuel volume ratio is 30. Margin of error 1.5%. aprompt -1.685672E-5 /K =arrow_forward
- The linear attenuation coefficient for 2.0-MeV gamma rays in water is 4.9 m-1 and 52 m-1 in lead. What thickness of water would give the same shielding for gamma rays as 15 mm of lead?arrow_forwardCadmium is used as a thermal neutron shield in an average flux of 101² neutrons/cm²/s. How long will it take to use up 10% of the 11$Cd atoms?arrow_forwardLead (density 11.34 g/cm³) and concrete (density 2.4 g/cm³) are highly effective materias in radiation shielding. a) What thickness of lead in cm is required to reduce the intensity of a 0.2 MeV gamma ray beam by a factor of 1000. b) What is the thickness of concrete in cm equivalent to that thickness of lead?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Modern PhysicsPhysicsISBN:9781111794378Author:Raymond A. Serway, Clement J. Moses, Curt A. MoyerPublisher:Cengage Learning
Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Classical Dynamics of Particles and SystemsPhysicsISBN:9780534408961Author:Stephen T. Thornton, Jerry B. MarionPublisher:Cengage Learning
College PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage Learning
College PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax College
Modern Physics
Physics
ISBN:9781111794378
Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Classical Dynamics of Particles and Systems
Physics
ISBN:9780534408961
Author:Stephen T. Thornton, Jerry B. Marion
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781285737027
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College