Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Chapter 21, Problem 44Q
To determine
The method by which the rapid flickering of an X-ray source provide evidence that the source is small.
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what is the answer for sub-item (b) if the radius of the neutron star is 6.676 km? (express your answer in the proper SI unit and without scientific notation)
(b)What is the average density of a neuron star that has the same mass as the sun but a radius of only 20.0 km?
what is the answer for sub-item (b) if the radius of the neutron star is 90.651 km? (express your answer in the proper SI unit and without scientific notation)
If a 1.40 MSun neutron star has a radius of 10.0 km, what is the radius (in km) of a 2.15 MSun neutron star? (Use the mass-radius relationship
R ∝ M−1/3)
What is the escape velocity (in km/s) from the surface of a 1.5 M neutron star? From a 3.0 M neutron star? (Hint: Use the formula for escape velocity,
Ve =
2GM
r
;
make sure to express quantities in units of meters, kilograms, and seconds. Assume a neutron star has a radius of 11 km and assume the mass of the Sun is 1.99 ✕ 1030 kg.)
1.5 M neutron star km/s3.0 M neutron star km/s
Chapter 21 Solutions
Universe: Stars And Galaxies
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