Concept explainers
(a)
The volume of the disk in cubic parsecs if the diameter of the disk is 50 kpc and thickness is 600 pc.
(a)
Answer to Problem 46Q
Solution:
The volume is
Explanation of Solution
Given data:
The diameter of the disk is 50 kpc and its thickness is 600 pc.
Formula used:
The expression for volume of a disk is:
Here
Explanation:
Recall the formula for volume of a disk.
Substitute 50,000 pc for
Conclusion:
The volume of the disk is
(b)
The volume of a sphere of radius 300 pc orbiting the Sun.
(b)
Answer to Problem 46Q
Solution:
The volume is
Explanation of Solution
Given data:
The radius of the sphere is 300 pc.
Formula used:
The expression for volume of a sphere is:
Here
Explanation:
Recall the expression for volume of a sphere.
Substitute 300 pc for
Conclusion:
The volume of sphere is
(c)
The probability of a supernova within the radius of the Sun, that is, 300 pc, if supernovae occur randomly throughout the volume of the galaxy. Also, calculate the time for these explosions if supernovae occur three times in a century.
(c)
Answer to Problem 46Q
Solution:
The probability is
Explanation of Solution
Given data:
The radius of the sun is
Formula used:
The expression to find the number of 300 pc spheres is:
Here
The expression for probability is:
Here
Explanation:
The volume of the sphere of radius
Recall the expression for number of spheres.
Substitute
Recall the expression for probability.
Substitute 11,000 for
If there are three supernovae then their occurrence will be:
Conclusion:
The probability of a supernova within 300 pc is
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Chapter 22 Solutions
UNIVERSE LL W/SAPLINGPLUS MULTI SEMESTER
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- If the active core of a galaxy contains a black hole of 106 MSun , what will the orbital distance be (in km) for matter orbiting the black hole with an orbital period of 1 hour?arrow_forwardIf a galaxy has an apparent radial velocity of 2,319 km/s and the Hubble constant is 70 km/s/Mpc, how far away is the galaxy?arrow_forward
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