Concept explainers
(a)
The semi-major axis of the star Sagittarius A* with orbital period
Answer to Problem 41Q
The length of the semi major axis of
Explanation of Solution
Given:
The orbital period of
The orbital period of
The mass of Sagittarius
Formula Used:
The expression for the length of the semi major axis is given by,
Calculation:
The value of one solar mass is
The length of the semi major axis of
Solve further as,
The length of the semi major axis of
Solve further as,
Conclusion:
Therefore, the length of the semi major axis of
(b)
The angular size of each orbits semi major axis as seen from Earth to the center of the galaxy. Also the reason for extremely high-resolution infrared images is required to observe the motions of stars.
Answer to Problem 41Q
The angular size of orbit of star
Explanation of Solution
Given:
The distance from the Earth to the center of the galaxy is
Formula Used:
The expression for the small angle formula is given by,
Here,
The formula to calculate the linear size of the orbit is given by,
Calculation:
The linear size of the orbit for
The linear size of the orbit for
The angular size of the orbit of
The angular size of the orbit of
The above given angles are very small and make it difficult to study the motion of the stars with very small angular sizes they require high resolution infrared imaging so that the far and tiny objects large wavelengths of radiation are used.
Conclusion:
The angular size of orbit of star
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Chapter 22 Solutions
Universe: Stars And Galaxies
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