### Angular Momentum and Neutron Star FormationIn this educational example, we explore the fascinating dynamics of a star's collapse into a neutron star and how its rotational characteristics change due to conservation of angular momentum. #### Scenario:- A star completes one revolution every 10 days.- Initial radius: \(7.00 \times 10^5 \) km.- The star collapses into a neutron star: - New radius: 20.0 km. - The star loses one half of its mass during the collapse.#### Question:**What is the new rate of revolutions per day?** (The moment of inertia of a star is given by \( \frac{2}{5} mr^2 \).)#### Multiple Choice Options:- \(3.13 \times 10^8 \) rev/day- \(3.20 \times 10^8 \) rev/day- \(3.32 \times 10^8 \) rev/day- \(1.70 \times 10^8 \) rev/day- \(2.45 \times 10^8 \) rev/day#### Explanation:To find the new revolutions per day, consider the conservation of angular momentum. Angular momentum \(L\) is conserved and is defined as \(L = I \omega\), where \(I\) is the moment of inertia and \(\omega\) is the angular velocity.1. **Initial Moment of Inertia (\(I_{\text{initial}}\)):** \[ I_{\text{initial}} = \frac{2}{5} m r_{\text{initial}}^2 \] Given: - Initial radius \( r_{\text{initial}} = 7.00 \times 10^5 \) km.2. **New Moment of Inertia (\(I_{\text{final}}\)):** \[ I_{\text{final}} = \frac{2}{5} \left( \frac{m}{2} \right) r_{\text{final}}^2 \] Given: - Final radius \( r_{\text{final}} = 20.0 \) km. - The mass is halved: \( \frac{m}{2} \).3. **Calculate Initial Angular Velocity (\(\omega_{\text{initial}}\)):** - The period (\(T\

Answered: Image /qna-images/answer/606578be-66f8-4e8a-a5f7-df321ba33e1d.jpg

A star spins one revolution every 10 days and its radius is 7.00*105 km. It then collapses and becomes a neutron star with a radius of 20.0 km. It also loses one half its mass during the collapse. ). What is the new revolutions /day? (The moment of inertia of a star is 2/5 mr²) O 3.13*108 rev/day O 3.20*108 rev/day O 3.32*108 rev/day 1.70*108 rev/day O 2.45*108 rev/day

A star spins one revolution every 10 days and its radius is 7.00105 km. It then collapses and becomes a neutron star with a radius of 20.0 km. It also loses one half its mass during the collapse. ). What is the new revolutions /day? (The moment of inertia of a star is 2/5 mr²) O 3.13108 rev/day O 3.20108 rev/day O 3.32108 rev/day 1.70108 rev/day O 2.45108 rev/day

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter34: Frontiers Of Physics

Section: Chapter Questions

Problem 21PE: Construct Your Own Problem Consider a star moving in a circular orbit at the edge at a galaxy....

See similar textbooks

Similar questions

6) How many 60 Watt bulbs would it take to equal the luminosity of the Sun? a. 1000 b. 2.4 X 10^26 c. 2.4 X 10^28 d. 6.67 X 10^26 e. 6.67 X 10^24
Fill in the blanks
1. What is escape velocity? 2. What does it mean to have a binding energy? 3. Under what conditions would you have to achieve in order for a satellite to escape the gravitational field of another body? 4. Why don't astronauts feel the effects of gravity while in orbit around Earth? 5. Why don't we feel the physical attraction from people around us, if there is a force of gravity between every obiect containing mass?
The name dark energy refers to the fact that a. it adds a negative term to the total energy of the Universe. b. it pervades the entire of the Universe, which is itself dark. c. it is concentrated in galaxies and galaxy clusters, but it is invisible. d. it is not detectable by any sort of light or other electromagnetic radiation. e. scientists are not sure what it is, so they use the term dark energy as a way to emphasize their ignorance.
Why don’t we see hydrogen Balmer lines in the spectra of stars with temperatures of 45,000 K? a. There is no hydrogen in stars this hot. b. The stars are hot enough that most of the hydrogen is ionized and the atoms cannot absorb energy. c. These stars are so cool that nearly all of the electrons in the hydrogen atom are in the ground state. d. Stars of this temperature are too cool to produce an absorption spectrum. e. Stars of this temperature are too hot to produce an absorption spectrum.
(a) Calculate the approximate age of the universe from the average value of the Hubble constant, H0=20km/s . Mly. To do this, calculate the time it would take to travel 0.307 Mpc at a constant expansion rate of 20 km/s. (b) If somehow acceleration occurs, would the actual age of the universe be greater or less than that found here? Explain.
The distance of a galaxy from our solar system is 10 Mpc. (a) What is the recessional velocity of the galaxy? (b) By what fraction is the starlight from this galaxy red shifted (that is, what is its z value)?
Construct Your Own Problem Consider a star moving in a circular orbit at the edge at a galaxy. Construct a problem in which you calculate the mass of that galaxy in kg and in multiples of the solar mass based on the velocity of the star and its distance from the center of the galaxy. Figure 34.26 Distances to nearby stars are measured using triangulation, also called the parallax method. The angle of line of sight to the star is measured at intervals six momma apart, and the distance is calculated by using the known diameter of the Earth's orbit. This can be done for stars up to about 500 ly away.
Construct Your Own Problem Consider a supermassive black hole near the center of a galaxy. Calculate the radius of such an object based on its mass. You must consider how much mass is reasonable for these large objects, and which is now nearly directly observed. (Information on black holes posted on the Web by NASA and other agencies is reliable, for example.)
Distances to the nearest stars (up to 500 by away) can be measured by a technique called parallax, as shown in Figure 34.26. What are the angles 1 and 2 relative to the plane of the Earth’s orbit for a star 4.0 by directly above the Sun?
What is critical temperature Tc? Do all materials have a critical temperature? Explain why or why not.
6. What kind of spectrum is shown below? a. black hole spectrum b. continuous spectrum c. absorption line spectrum d. bright line emission spectrum e. all of these