Concept explainers
(a)
The average speed of a hydrogen atom having mass =
(a)
Answer to Problem 47Q
Solution:
Explanation of Solution
Given data:
For present-day Sun,
Mass of hydrogen atom is
Formula used:
Write the expression for the average speed for a gas atom or molecule.
Here,
Explanation:
Recall the equation for the average speed.
Substitute
Conclusion:
Therefore, the average speed of the hydrogen atom is
(b)
The average speed of a hydrogen atom having mass =
(b)
Answer to Problem 47Q
Solution:
Explanation of Solution
Given data:
For
Mass of hydrogen atom is
Formula used:
Write the expression for the average speed for a gas atom or molecule.
Here,
Explanation:
Recall the equation for the average speed.
Substitute
Conclusion:
Therefore, the average speed of the hydrogen atom in the atmosphere of the red giant is
(c)
The extent to which the present day Sun and a
(c)
Answer to Problem 47Q
Solution: In both cases, the value of the escape speed is higher than the average speed of the atoms but is close in the case of a red giant. Therefore, one can say that for speed above the average speed, hydrogen will leave the red giant.
Explanation of Solution
Introduction:
The escape velocity is the minimum velocity required to escape the gravitational attraction of a planet or star.
Explanation:
Calculate the escape velocity for both cases.
For present-day Sun,
Write the expression for the escape speed.
Here,
Recall the equation for the escape speed.
Substitute
Calculate the escape speed for the red giant;
Recall the equation for the escape speed.
Substitute
The escape velocity for present-day Sun is
Conclusion:
Hence, both the Sun and the red giant will retain hydrogen in their cores but the red giant is more likely to lose that hydrogen as compared to the Sun.
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Chapter 19 Solutions
Universe
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