Concept explainers
(a)
The average separation between the two stars of the overcontact binary system W Ursae in kilometers. It is given that the two stars have mass 0.99
(a)
Answer to Problem 42Q
Solution:
Explanation of Solution
Given data:
The mass of two stars are 0.99
Formula used:
Write the expression for Newton’s form of Kepler’s third law:
Here,
In case of binary stars,
Explanation:
It is known that the period of the binary star system W Ursae is of 8 hours. Convert this time period in years.
Now, recall the expression for Newton’s form of Kepler’s third law.
Substitute
Convert
So, the distance between the two binary stars is,
Conclusion:
Hence, the value of average separation between the stars is
(b)
To check: That W Ursae is an overcontact binary star system, using the radii of its two stars given as
(b)
Answer to Problem 42Q
Solution:
W Ursae is an overcontact binary star system since the distance between the two binary stars in is almost comparable to the sum of their individual radii.
Explanation of Solution
Introduction:
An overcontact binary star system is one where the two stars are in contact with each other.
The radii of the two stars of W Ursae are
Explanation:
Caluclate the sum of the two given radii as ‘
Convert unit of
Now, compare the value of
Conclusion:
Hence, it is found that the W Ursae is an overcontact binary star system as the sum of the radii of the two stars is almost the same as the distance between them.
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Chapter 19 Solutions
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