Concept explainers
(a)
The Spectral class for the brown dwarf
(a)
Answer to Problem 54Q
Solution:
L
Explanation of Solution
Given data:
The temperature of the brown dwarf star is
Introduction:
On the basis of temperature of the surface of stars, they are divided into different spectral classes.
Explanation:
Refer the table 17-2. The spectral sequence, the temperature and the brown dwarf lies to the Spectral class L.
Conclusion:
The temperature and the brown dwarf lie to the spectral class of L.
(b)
The radius (in kilometers) of
(b)
Answer to Problem 54Q
Solution:
Explanation of Solution
Given data:
Brown dwarf has a luminosity of
Formula used:
The relation between luminosity of different stars is:
Here,
Explanation:
The Sun’s surface temperature is,
The relation between luminosity of different stars is:
Substitute
Further solve,
Refer to Appendix 6, the value of Solar radius is
Therefore,
Therefore, the value of the radius in kilometer is
Now, refer to appendix 2, the value of the diameter of Jupiter is
Therefore, the radius of Jupiter is:
Expression for radius is:
Use this expression to determine the radius of Jupiter.
The radius of
Conclusion:
The name Dwarf is not justified as the radius is not much smaller, and also the value of the radius is
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Chapter 17 Solutions
Universe
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