Concept explainers
(a)
Themass of the core.
Answer to Problem 45Q
The mass of the core in kilograms is
Explanation of Solution
Given:
The diameter of the core is,
The density of the core is,
Formula used:
The expression for the volume of the core is given by,
Here,
The expression for the density of the core is given by,
Calculation:
The radius of the coreis calculated as,
The volume of the core is calculated as,
The mass of the core is calculated as,
Conclusion:
The mass of the core in kilograms is
(b)
Theforce of gravity on a
Answer to Problem 45Q
The force of gravity on the surface of the core is
Explanation of Solution
Given:
The radius of the core is,
The mass of the object is,
Formula used:
The gravitational force between the two bodies is given by,
Here,
Calculation:
The gravitational force between the two bodies is calculated as,
The ratio of the gravitational force on the surface of the core of the supernova and on the surface of the Earth is calculated as,
Conclusion:
The force of gravity on the surface of the core is
(c)
The escape speed from the surface of the star’s core.
Answer to Problem 45Q
The escape speed from the surface of the star’s core is
Explanation of Solution
Given:
The radius of the core is,
The mass of the object is,
Formula used:
The escape velocity is given by,
Calculation:
The escape velocity is calculated as,
Solve further,
Conclusion:
The escape speed from the surface of the star’s core is
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Chapter 20 Solutions
UNIVERSE (LOOSELEAF):STARS+GALAXIES
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- Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning