Concept explainers
(a)
The equilibrium ratio of population of
(a)
Answer to Problem 62P
The equilibrium ratio of population of
Explanation of Solution
Write the expression for the number of atoms in a state of energy
Here,
Write the expression for population of atoms in
Here,
Write the expression for population of atoms in
Here,
Divide expressions (II) by (III).
Write the expression to convert temperature from Celsius scale to Kelvin scale.
Here,
Write the expression for energy difference between energies
Conclusion:
Substitute
Substitute
Substitute
Therefore, the equilibrium ratio of population of
(b)
The temperature for which the distribution shows a
(b)
Answer to Problem 62P
The temperature for which the distribution shows a
Explanation of Solution
It is given that the number of atoms in the upper state is
Rewrite expression for
Take logarithm of above expression.
Use expression (VII) to find
Conclusion:
Substitute
Therefore, the temperature for which the distribution shows a
(c)
The reason why
(c)
Answer to Problem 62P
For
Explanation of Solution
The energy difference between states
Rewrite expression for
In the above equation, temperature is always positive and hence the resultant population ratio will be less than one or it will be a smaller value. So a population cannot happen in thermal equilibrium.
Conclusion:
For
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Chapter 42 Solutions
Physics For Scientists And Engineers With Modern Physics, 9th Edition, The Ohio State University
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