21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 18, Problem 45QP
To determine
The mass of the black hole from the given information.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
How can black holes lead to parallel universes? And how do black holes lead to parallel universes?
Calculate the Schwarzschild Radius for the following:
1. a black hole with the mass of you (estimate your mass to be 51.8 kg)
I'm stumped on this question: A clump of matter does not need to be extraordinarily dense in order to have an escape velocity greater than the speed of light, as long as its mass is large enough. You can use the formula for the Schwarzschild radius RS to calculate the volume, 4/3 πRS^3, inside the event horizon of a black hole of mass M. What does the mass of a black hole need to be in order for its mass divided by its volume to be equal to the density of water (1g/cm^3)?
I'm not sure where to begin in findng the answer. It feels as if I'm missing information.
Chapter 18 Solutions
21st Century Astronomy
Ch. 18.1 - Prob. 18.1CYUCh. 18.2 - Prob. 18.2CYUCh. 18.3 - Prob. 18.3CYUCh. 18.4 - Prob. 18.4CYUCh. 18 - Prob. 1QPCh. 18 - Prob. 2QPCh. 18 - Prob. 3QPCh. 18 - Prob. 4QPCh. 18 - Prob. 5QPCh. 18 - Prob. 6QP
Ch. 18 - Prob. 7QPCh. 18 - Prob. 8QPCh. 18 - Prob. 9QPCh. 18 - Prob. 10QPCh. 18 - Prob. 11QPCh. 18 - Prob. 12QPCh. 18 - Prob. 13QPCh. 18 - Prob. 14QPCh. 18 - Prob. 15QPCh. 18 - Prob. 16QPCh. 18 - Prob. 17QPCh. 18 - Prob. 18QPCh. 18 - Prob. 19QPCh. 18 - Prob. 20QPCh. 18 - Prob. 21QPCh. 18 - Prob. 22QPCh. 18 - Prob. 23QPCh. 18 - Prob. 24QPCh. 18 - Prob. 25QPCh. 18 - Prob. 26QPCh. 18 - Prob. 27QPCh. 18 - Prob. 28QPCh. 18 - Prob. 29QPCh. 18 - Prob. 30QPCh. 18 - Prob. 31QPCh. 18 - Prob. 32QPCh. 18 - Prob. 33QPCh. 18 - Prob. 34QPCh. 18 - Prob. 35QPCh. 18 - Prob. 36QPCh. 18 - Prob. 37QPCh. 18 - Prob. 38QPCh. 18 - Prob. 39QPCh. 18 - Prob. 40QPCh. 18 - Prob. 41QPCh. 18 - Prob. 42QPCh. 18 - Prob. 43QPCh. 18 - Prob. 44QPCh. 18 - Prob. 45QP
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
- The next step in deciding whether the object in Exercise 25.25 is a black hole is to estimate the density of this mass. Assume that all of the mass is spread uniformly throughout a sphere with a radius of 20 lighthours. What is the density in kg/km3? (Remember that the volume of a sphere is given by V=43R3 .) Explain why the density might be even higher than the value you have calculated. How does this density compare with that of the Sun or other objects we have talked about in this book?arrow_forwardan introduction on what is the event horizon of a black holes?arrow_forwardOnce again in this chapter, we see the use of Kepler’s third law to estimate the mass of supermassive black holes. In the case of NGC 4261, this chapter supplied the result of the calculation of the mass of the black hole in NGC 4261. In order to get this answer, astronomers had to measure the velocity of particles in the ring of dust and gas that surrounds the black hole. How high were these velocities? Turn Kepler’s third law around and use the information given in this chapter about the galaxy NGC 4261-the mass of the black hole at its center and the diameter of the surrounding ring of dust and gas-to calculate how long it would take a dust particle in the ring to complete a single orbit around the black hole. Assume that the only force acting on the dust particle is the gravitational force exerted by the black hole. Calculate the velocity of the dust particle in km/s.arrow_forward
- A friend of yours who has watched many Star Trek episodes and movies says, “I thought that black holes pulled everything into them. Why then do astronomers think that black holes can explain the great outpouring of energy from quasars?” How would you respond?arrow_forwardTo what does cold refer to the term "cold dark matter"? Why do models of large-scale structure agree best with the dark matter being "cold"?arrow_forwardAs a mass m of gas falls into a black hole, at most 0.1mc2 is likely to emerge as radiation; the rest is swallowed by the black hole. Show the Eddington luminosity for a black hole of mass M is equivalent to 2*10-9 Mc2yr-1. Explain why we expect the black hole's mass to grow by at least a factor of e every 5*107 years. Where Edding Luminicity is defined as LE=(4piGMmpc)/(sigmaT), where G is the gravitational constant, M is the mass of the black hole, mp is the mass of a proton, c is the speed of light, and sigmaT is Thomson scattering where sigmaT=6.653*10-25 cm2.arrow_forward
- You discover by dropping particles into it that the Event Horizon (Schwartzschild Radius) of a black hole is 171 km. How massive is it? (enter just the number in solar masses)arrow_forwardHow can we “observe” a black hole if neither matter nor radiation can escape from it?arrow_forwardSince the force of gravity a significant distance away from the event horizon of a black hole is the same as that of an ordinary object of the same mass, Kepler’s third law is valid. Suppose that Earth collapsed to the size of a golf ball. What would be the period of revolution of the Moon, orbiting at its current distance of 400,000 km? Use Kepler’s third law to calculate the period of revolution of a spacecraft orbiting at a distance of 6000 km.arrow_forward
- How do black holes form, and what are the implications of their existence on our understanding of gravity and the structure of the universe?arrow_forwardAround 2.5 centuries ago, several physicists of the time came up with the notion of a dark star. This was a star so dense, with so much gravity, that not even light could escape. The calculations used Newtonian mechanics. In class, we calculated the escape speed from the surface of the earth or the distance from the sun, and the mass of the planet or star. Here, the process is partially reversed. Calculate the dark star radius from the mass of the star and the escape speed. Answer in kilometers. c = 3*108 m/s M = 2.4*1030 kg G = 2/3 * 10-10 N*m2/kg2arrow_forwardWhat’s the history behind gravitational waves?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStaxStars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningStars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
- Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
General Relativity: The Curvature of Spacetime; Author: Professor Dave Explains;https://www.youtube.com/watch?v=R7V3koyL7Mc;License: Standard YouTube License, CC-BY