Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 21, Problem 15Q
To determine
The maximum mass of a neutron star and the effect of neutrons repulsion force on this mass.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
The typical core-collapse supernova has an energy budget of about 1046 J. This energy comes
from the gravitational potential energy of an inner core with mass Mic, which collapses from an
initial radius of 5 x 106 m down to the final radius of 50 km. Estimate Mic, in solar masses, for
this to be a realistic energy source of the core-collapse supernova. You may assume that the
density before the collapse is uniform.
Discuss briefly how a Type la supernova is different from a core-collapse supernova from a
massive star?
2. Consider a neutron star of radius of 10 km and a mass of 1.4 M⊙ that has a surface layer of pure 1H.
(a) For the given parameters, compute the luminosity and wavelength of peak emission of a neutron star shining at Eddington Luminosity in the rest frame of the neutron star. Assume black body emission.
(b) What is the impact of a) the gravitational redshift and b) the time delay, both caused by general relativity, on the observed wavelength?
(c) What is the wavelength and luminosity seen by an observer at large distance (much larger than neutron star radius)?
6
Chapter 21 Solutions
Universe: Stars And Galaxies
Ch. 21 - Prob. 1QCh. 21 - Prob. 2QCh. 21 - Prob. 3QCh. 21 - Prob. 4QCh. 21 - Prob. 5QCh. 21 - Prob. 6QCh. 21 - Prob. 7QCh. 21 - Prob. 8QCh. 21 - Prob. 9QCh. 21 - Prob. 10Q
Ch. 21 - Prob. 11QCh. 21 - Prob. 12QCh. 21 - Prob. 13QCh. 21 - Prob. 14QCh. 21 - Prob. 15QCh. 21 - Prob. 16QCh. 21 - Prob. 17QCh. 21 - Prob. 18QCh. 21 - Prob. 19QCh. 21 - Prob. 20QCh. 21 - Prob. 21QCh. 21 - Prob. 22QCh. 21 - Prob. 23QCh. 21 - Prob. 24QCh. 21 - Prob. 25QCh. 21 - Prob. 26QCh. 21 - Prob. 27QCh. 21 - Prob. 28QCh. 21 - Prob. 29QCh. 21 - Prob. 30QCh. 21 - Prob. 31QCh. 21 - Prob. 32QCh. 21 - Prob. 33QCh. 21 - Prob. 34QCh. 21 - Prob. 35QCh. 21 - Prob. 36QCh. 21 - Prob. 37QCh. 21 - Prob. 38QCh. 21 - Prob. 39QCh. 21 - Prob. 40QCh. 21 - Prob. 41QCh. 21 - Prob. 42QCh. 21 - Prob. 43QCh. 21 - Prob. 44QCh. 21 - Prob. 45QCh. 21 - Prob. 46QCh. 21 - Prob. 47QCh. 21 - Prob. 48QCh. 21 - Prob. 49QCh. 21 - Prob. 50QCh. 21 - Prob. 51QCh. 21 - Prob. 52QCh. 21 - Prob. 53QCh. 21 - Prob. 54QCh. 21 - Prob. 55QCh. 21 - Prob. 56QCh. 21 - Prob. 57QCh. 21 - Prob. 58QCh. 21 - Prob. 59QCh. 21 - Prob. 60QCh. 21 - Prob. 61QCh. 21 - Prob. 62QCh. 21 - Prob. 63QCh. 21 - Prob. 64QCh. 21 - Prob. 65QCh. 21 - Prob. 66QCh. 21 - Prob. 67QCh. 21 - Prob. 68QCh. 21 - Prob. 69QCh. 21 - Prob. 70QCh. 21 - Prob. 71QCh. 21 - Prob. 72QCh. 21 - Prob. 73QCh. 21 - Prob. 74QCh. 21 - Prob. 75Q
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- Problem 3. Consider a flat, single component universe. 1. For a light source at redshift z that is observed at time to, show that z changes at a rate dz dto = = Ho(1 + 2) — Ho(1+2)³(¹+w)/2 (2.1) 2. For what values of w does the observed redshift increase with time? 3. Assuming the single component is matter and Ho = 68 km/s/Mpc, you observe a galaxy at z = 1. Using Equation 2.1, determine how long you will have to keep observing the galaxy in order to see its redshift change by 1 part in 106.arrow_forwardDifferential Equation "Rectilinear motion And Escape Velocity " (TOPIC) Please show solutions Thankyouu!arrow_forwarddouble line The velocity curve spectroscopic binary is shown in the sketch. The system is viewed edge-on, i.e., with an inclination angle of i = 90°, so that the maximum possible Doppler shifts for this system are observed. for a 400 So = U, Ani 300 200 no - V Ain i 100 -100 -200 -300 400 • 1 2 3 . S 6 7 8 10 Time (days) Find the mass ratio, m1/m2, of the stars. Express your answer as a fraction like a/b Doppler Velocityarrow_forward
- Problem 10. The redshift is defined to be the quantity Job – Xem Xem (5.1) where Aob and Aem are respectively the wavelengths at which radiation is observed and emitted. Find the corresponding definition in terms of observed and emitted frequencies fob and fem.arrow_forwardThe expanding universe is carrying distant objects away from each other at a rate proportional to their separations. We use the Doppler effect observed in spectra of distant galaxies and quasars to calculate recession speeds. For the most distant objects recession speeds approach c, and therefore, the relativistic Doppler shift expression must be used. We define the redshift, z, as the fractional change in wavelength. a) The most distant quasar currently known is ULAS J1120+0641, discovered with the UK Infrared Telescope on Mauna Kea. It has a redshift of 7.1. Calculate its radial velocity in terms of v/c. b) Determine the distance to this quasar. c) At what wavelength would the Ha line (656.28 nm) be observed for this quasar?arrow_forwardIn the Check Your Learning section of Example 27.1, you were told that several lines of hydrogen absorption in the visible spectrum have rest wavelengths of 410 nm, 434 nm, 486 nm, and 656 nm. In a spectrum of a distant galaxy, these same lines are observed to have wavelengths of 492 nm, 521 nm, 583 nm, and 787 nm, respectively. The example demonstrated that z=0.20 for the 410 nm line. Show that you will obtain the same redshift regardless of which absorption line you measure.arrow_forward
- The Sun and all Main Sequence stars derive their luminosity by fusing hydrogen to helium; in particular 4 1H ® 1 4He + Energy (photons) The mass of a proton is 1.0078 AMU, while the mass of a helium nucleus is 4.0026 AMU. a) How much mass is ``lost'' (in AMU and kg) in fusing four H atoms to one helium? This is called the mass defect. b) Mass isn't really lost, of course. It is converted to energy via E=mc2. How much energy in joules (J) is liberated in a single reaction? c) How many reactions per second are required to account for the entire luminosity of the Sun?arrow_forward*39 Will the universe continue to expand forever? To attack this question, assume that the theory of dark energy is in error and that the recessional speed v of a galaxy a distance r from us is determined only by the gravitational interaction of the matter that lies inside a sphere of radius r centered on us. If the total mass inside this sphere is M, the escape speed v, from the sphere is v. = V2GMIT (Eq. 13-28). (a) Show that to prevent unlimited expansion, the aver- age density p inside the sphere must be at least equal to ЗН 87G (b) Evaluate this "critical density" numerically; express your an- swer in terms of hydrogen atoms per cubic meter. Measurements of the actual density are difficult and are complicated by the pres- ence of dark matter.arrow_forwardStephen Hawking’s derivation of the black hole temperature used the fact that the black hole’s entropy is given by S = 8π2GM2k/hc. Complete the derivation using the thermodynamic defi nition of temperature 1/T = δS/δU. Assume that the black hole’s energy is entirely mass-energy, that is, U = Mc2.arrow_forward
- esc a) 10 points) Gravitational Time Dilation. The escape velocity from the surface (radius r) of a star or planet of mass M is given by the formula v = (2GM/r). Use this expression to write the time-dilation fraction, At/t, in terms of the ratio of vesc to the speed of light, c. Hint: This is just a simple exercise in substitution. 5.98 x 1024 kg b) (10 points) Extra Lifetime on the Surface of Earth. The Earth has mass MEarth and radius REarth 6.38 x 10 m. What is the fractional time-dilation (At/t) for someone on the Earth's surface? How much longer (At) is a typical lifetime on the surface of Earth, compared to someone in deep space, far away from Earth? Assume a typical human life span of t = 80 years. Iarrow_forwardWhen a star erupts in a supernova explosion, huge numbers of electron neutrinos are formed in nuclear reactions. Such neutrinos from the 1987A supernova in the relatively nearby Magellanic Cloud were observed within hours of the initial brightening, indicating they traveled to earth at approximately the speed of light. Explain how this data can be used to set anupper limit on the mass of the neutrino, noting that if the mass is small the neutrinos could travel very close to the speed of light and have a reasonable energy (on the order of MeV).arrow_forwardWhat is a rest-frame spectrum of a typical BCG?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
Modern PhysicsPhysicsISBN:9781111794378Author:Raymond A. Serway, Clement J. Moses, Curt A. MoyerPublisher:Cengage Learning
Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax
Modern Physics
Physics
ISBN:9781111794378
Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning