Concept explainers
(a)
To compare the ratios
(a)
Answer to Problem 8.10P
For all the given temperatures,
Explanation of Solution
In the case under consideration, the subscript I stands for neutral helium, II stands for singly ionized helium, and III sands for the completely ionized helium atom.
Given that the ionization energies
Write the expression for the Saha equation in terms of the electron pressure.
Here,
Rewrite equation (I) for determining the required ratios.
Conclusion:
Substitute
Similarly the values of the ratios
From the table it is clear that the ratio
Therefore, for all the given temperatures,
(b)
To show that
(b)
Answer to Problem 8.10P
The ratio
Explanation of Solution
Given ratio expression is;
Take
Multiply and divide the third term in the denominator in equation (V) with
Equation (VI) is the form of the equation (IV) written in terms of the ratios
Conclusion:
Therefore, the ratio
(c)
To plot the graph of
(c)
Answer to Problem 8.10P
The plot the graph of
Explanation of Solution
The expression for
From the obtained values of
With the given values of electron pressure, ionization energies and partition functions for the neutral helium atom and singly ionized helium atom, the ratio
Conclusion:
The graph of
From the graph it can be noted that when the temperature corresponding to the partial ionization of the neutral helium is about
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Chapter 8 Solutions
EBK AN INTRODUCTION TO MODERN ASTROPHYS
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