Introduction To Health Physics
5th Edition
ISBN: 9780071835275
Author: Johnson, Thomas E. (thomas Edward), Cember, Herman.
Publisher: Mcgraw-hill Education,
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Question
Chapter 2, Problem 2.31P
(a)
To determine
What is the mean power density (mW/cm2), at a distance of 50 km if a radio station transmits at a power of 50,000 W. Assuming the
(b)
To determine
What is the maximum electric field strength at that distance?
(c)
To determine
What is the maximum magnetic field strength at that distance?
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The ICNIRP also has guidelines for magnetic-field exposure for the general public. In the frequency range of 25 Hz to 3 kHz, this guideline states that the maximum allowed magnetic-field amplitude is 5>f T, where f is the frequency in kHz. Which is a more stringent limit on allowable electromagnetic-wave intensity in this frequency range: the electric-field guideline or the magnetic-field guideline? (a) The magnetic-field guideline, because at a given frequency the allowed magnetic field is smaller than the allowed electric field. (b) The electric-field guideline, because at a given frequency the allowed intensity calculated from the electric-field guideline is smaller. (c) It depends on the particular frequency chosen (both guidelines are frequency dependent). (d) Neither—for any given frequency, the guidelines represent the same electromagneticwave intensity
A receiver that is a 1000 km from a radio wave transmitter records an intensity of 2000 W/m2forincident radio waves.(a) What is the power of radio waves emitted by the transmitter?
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(d) Determine the wavelength of a 30 MHz radio wave, now travelling in water (speed of EMwaves in water = 2.26 x 108 m/s).
Problem 7: If you wish to observe features that are around the size of atoms, say 8.5 × 10-10 m, with electromagnetic radiation, the radiation must have a wavelength of about the size of the atom itself.
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Chapter 2 Solutions
Introduction To Health Physics
Ch. 2 - Two blocks of mass 0.1 kg and 0.2 kg approch each...Ch. 2 - A bullet whose mass is 50 g travels at a velocity...Ch. 2 - Compute the mass of the Earth, assuming it to be a...Ch. 2 - An automobile weighing 2000 kg and going at a...Ch. 2 - A small electrically charged sphere of mass 0.1 g...Ch. 2 - A capacitor has a capacitance of 10F . How much...Ch. 2 - A small charged particle whose mass is 0.01 g...Ch. 2 - Prob. 2.8PCh. 2 - Prob. 2.9PCh. 2 - Prob. 2.10P
Ch. 2 - Prob. 2.11PCh. 2 - Prob. 2.12PCh. 2 - Prob. 2.13PCh. 2 - Prob. 2.14PCh. 2 - Prob. 2.15PCh. 2 - A current of 25 mA flows through a 25-gauge wire,...Ch. 2 - An electron starts at rest on the negative plate...Ch. 2 - Prob. 2.18PCh. 2 - Prob. 2.19PCh. 2 - Prob. 2.20PCh. 2 - Prob. 2.21PCh. 2 - Prob. 2.22PCh. 2 - Prob. 2.23PCh. 2 - (a) A 1000-MW(e) nuclear power plant operates at a...Ch. 2 - Prob. 2.25PCh. 2 - Prob. 2.26PCh. 2 - Prob. 2.27PCh. 2 - The specific heat of water in the English system...Ch. 2 - Prob. 2.29PCh. 2 - Prob. 2.30PCh. 2 - Prob. 2.31PCh. 2 - Prob. 2.32PCh. 2 - How many cubic meters of water must fall over a...Ch. 2 - (a) Calculate the speed of a 25-MeV proton. (b)...Ch. 2 - Prob. 2.35PCh. 2 - Prob. 2.36PCh. 2 - Calculate the speed of a (a) 0.5-MeV electron and...Ch. 2 - How much sub-butuminous coal (20,000 kJ/kg) would...Ch. 2 - Prob. 2.40PCh. 2 - How much oil (138,690 Btu/gal) would it take to...Ch. 2 - How much oil (138,690 Btu/gal) would it take to...Ch. 2 - Prob. 2.43PCh. 2 - Prob. 2.44PCh. 2 - Prob. 2.45PCh. 2 - Prob. 2.46PCh. 2 - Prob. 2.47PCh. 2 - Prob. 2.48PCh. 2 - Prob. 2.49P
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