Concept explainers
(a)
The fraction of the galaxy’s volume is occupied by stars.
(a)
Answer to Problem 34PQ
The fraction of the galaxy’s volume is occupied by stars is
Explanation of Solution
Write the equation of fraction of galaxy’s volume is occupied by stars.
Here,
Write the expression for the volume of star.
Here,
Rewrite the expression for the fraction.
Conclusion:
Substitute
Thus, the fraction of the galaxy’s volume is occupied by stars is
(b)
The mean free path of a star through galaxy.
(b)
Answer to Problem 34PQ
The mean free path of a star through galaxy is
Explanation of Solution
Write the equation of mean free path.
Here,
Conclusion:
Substitute,
Thus, the mean free path of a star through galaxy is
(c)
The probability of collision.
(c)
Answer to Problem 34PQ
The probability of collision is
Explanation of Solution
Write the equation for the probability.
Here,
Conclusion:
Substitute
Therefore, the probability of collision is
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Chapter 20 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning