College Physics (10th Edition)
10th Edition
ISBN: 9780321902788
Author: Hugh D. Young, Philip W. Adams, Raymond Joseph Chastain
Publisher: PEARSON
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Chapter 30, Problem 49P
(a)
To determine
An expression for the critical density of the universe in the number of H atoms per cubic meter assuming that the whole universe is only hydrogen.
(b)
To determine
The average number of atoms in a room of dimension
(c)
To determine
Compare the number of atoms calculated in section (b) with the practical number of atoms generally found in a room.
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Suppose you are designing a proton decay experiment and you can detect 50 percent of the proton decays in a tank of water. (a) How many kilograms of water would you need to see one decay per month, assuming a lifetime of 1031 y ?
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Chapter 30 Solutions
College Physics (10th Edition)
Ch. 30 - Prob. 1CQCh. 30 - Prob. 2CQCh. 30 - True or false? During one half-life, the mass of a...Ch. 30 - Changing the temperature of atoms affects their...Ch. 30 - Prob. 5CQCh. 30 - Prob. 6CQCh. 30 - Prob. 7CQCh. 30 - Prob. 8CQCh. 30 - Prob. 9CQCh. 30 - Prob. 10CQ
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