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The density of Neutron stars of masses
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Answer to Problem 4P
The density of Neutron stars of masses
Explanation of Solution
Necessary data is obtained from problem 2. It is found that from problem 2, radius of Neutron star having mass
Write the relation between mass and density.
Here,
Write the equation to find
Here,
Rewrite the equation for
Rewrite the above equation by substituting
Here,
Rewrite equation (I) by substituting
Conclusion:
Case 1: Neutron star of mass
Substitute
Case 2: Neutron star of mass
Substitute
Therefore, the density of Neutron stars of masses
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Chapter 14 Solutions
Foundations of Astronomy (MindTap Course List)
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- An astronomical image shows two objects that have the same apparent magnitude, i.e., the same brightness. However, spectroscopic follow up observations indicate that while one is a star that is within our galaxy, at a distance dgal away, and has the same luminosity as the Sun, the other is a quasar and has 100x the luminosity of the entire Milky Way galaxy. What is the distance to the quasar? (You may assume, for this rough calculation, that the Milky Way has 1011 stars and that they all have the luminosity as the Sun.) Give your response in Mpc. Value: dgal = 49 pcarrow_forwardIf 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/sarrow_forwardA star has initially a radius of 680000000 m and a period of rotation about its axis of 26 days. Eventually it changes into a neutron star with a radius of only 40000 m and a period of 0.2 s. Assuming that the mass has not changed, find Assume a star has the shape of a sphere. (Suggestion: do it with formula first, then put the numbers in) [Recommended time : 5-8 minutes] (a) the ratio of initial to final angular momentum (Li/Lf) Oa. 3.25E+15 Ob. 25.7 Oc. 0.0389 Od. 3.08E-16 (b) the ratio of initial to final kinetic energy Oa. 2.74E-23 Ob. 437000 Cc. 2.29E-6 FUJITSUarrow_forward
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