College Physics
2nd Edition
ISBN: 9780134601823
Author: ETKINA, Eugenia, Planinšič, G. (gorazd), Van Heuvelen, Alan
Publisher: Pearson,
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 25, Problem 41GP
To determine
The average density of the Milky Way galaxy by assuming that it contains about
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Astronomers are always seeking to build bigger, more powerful telescopes, which will allow them to study faint galaxies that are very far away. Which of the following is the main reason they're so obsessed with studying very distant galaxies?
Group of answer choices
Light traveled much faster during the early history of the universe, so we can study how the speed of light has changed through time.
Very distant galaxies are more likely to contain planets than the Milky Way is, so we have a better chance of detecting life in those galaxies than we do in our own galaxy.
Since the light from these galaxies took so long to reach us, we're seeing them as they were when the universe was very young.
Strangely, distant galaxies are more like our Milky Way than the Milky Way's `neighbor' galaxies are, and astronomers would like to figure out why this is.
The mass density of our universe is measured to be about 10-29 kg/m3. If an arbitrary point is chosen as the center, how large is the radius of a spherical surface centered at the point so that the mass enclosed in the surface will become a blackhole observed by someone outside the surface?
A. 4.2 trillion light years
B. 420 billion light years
C. 42 billion light years
D. 4.2 billion light years
Is the answer D? Thanks!
Part 1. Stellar Mass Black Holes
These are the collapsed cores of massive stars which end their life in supernova explosions. The
stellar core can no longer use nuclear fusion to hold up the immense gravity, and collapses until
its escape velocity rises higher than the speed of light. Voila! A black hole is formed.
Part A: The Schwarzschild Radius
The Schwarzschild Radius is defined as:
2GM
(1)
=
c2
where r, is the Schwarzschild radius, G is the gravitational constant, M is the mass of the black
hole, and c is the speed of light.
1. Let's say we have a black hole with a mass 10 times that of the Sun (the Sun's mass is 2 x
1030 kg, so the mass of the black hole is then 2 x 1031 kg). Using the definitions for G and
c, what would the Schwarzschild radius of this black hole be?
2. If the radius of the Sun is 7 x 108 m, how does the black hole's radius compare? (Divide
the radius of the Sun by the Schwarzschild radius). Your answer should be in the form of
times smaller/bigger than the…
Chapter 25 Solutions
College Physics
Ch. 25 - Review Question 25.1 What is the difference...Ch. 25 - Review Question 25.2 What needs to happen to...Ch. 25 - Review Question 25.3 How are GPS and radar...Ch. 25 - Review Question 25.4 If the frequency of one...Ch. 25 - Review Question 25.5 Electromagnetic waves are...Ch. 25 - Review Question 25.6 Explain why polarizing...Ch. 25 - Multiple Choice Questions The fact that light can...Ch. 25 - Multiple Choice Questions What does a beam of...Ch. 25 - Multiple Choice Questions What does Faraday's law...Ch. 25 - Multiple Choice Questions
4. Maxwell's hypothesis...
Ch. 25 - Multiple Choice Questions What does a simple...Ch. 25 - Multiple Choice Questions An electrically charged...Ch. 25 - Prob. 7MCQCh. 25 - Multiple Choice Questions If the amplitude of an E...Ch. 25 - Multiple Choice Questions
9. You notice that...Ch. 25 - Multiple Choice Questions You have two green...Ch. 25 - Prob. 11CQCh. 25 - Conceptual Questions What are two models that...Ch. 25 - Conceptual Questions
13. Summarize Maxwell's...Ch. 25 - Conceptual Questions What testable predictions...Ch. 25 - Conceptual Questions
15. Describe the conditions...Ch. 25 - Conceptual questions
16. Explain how radar works...Ch. 25 - Conceptual Questions
17. What determines the...Ch. 25 - Conceptual Questions How was the hypothesis that...Ch. 25 - Conceptual Questions
19. What is the difference...Ch. 25 - Conceptual Questions
20. How do polarized glasses...Ch. 25 - Conceptual Questions You bought a pair of glasses...Ch. 25 - Conceptual Questions Why. when we use polarized...Ch. 25 - Conceptual Questions 23 How does a polarizer for...Ch. 25 - Conceptual Questions
24. What is an LCD and how...Ch. 25 - Prob. 25CQCh. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - Prob. 8PCh. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.1 and 25.2 Polarization of waves and Discovery...Ch. 25 - 25.3 Applications of electromagnetic waves 11 EST...Ch. 25 - 25.3 Applications of electromagnetic waves
12.*...Ch. 25 - 25.3 Applications of electromagnetic waves
13. *...Ch. 25 - 25.3 Applications of electromagnetic waves *...Ch. 25 - 25.3 Applications of electromagnetic waves * TV...Ch. 25 - 25.3 Applications of electromagnetic waves **...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - Prob. 18PCh. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - Prob. 25PCh. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - 25.4 and 25.5 Frequency, wavelength, and the...Ch. 25 - Prob. 29PCh. 25 - 25.6 Polarization and light reflection
33. * An...Ch. 25 - 25.6 Polarization and light reflection * BIO...Ch. 25 - 25.6 Polarization and light reflection
35. * Two...Ch. 25 - 25.6 Polarization and light reflection * Light...Ch. 25 - Polarization and light reflection 37 * Light...Ch. 25 - 25.6 Polarization and light reflection
38.*...Ch. 25 - 25.6 Polarization and light reflection
40.* A beam...Ch. 25 - Prob. 41GPCh. 25 - * BIO EST Human vision power sensitivity A rod in...Ch. 25 - Prob. 44GPCh. 25 - Prob. 45GPCh. 25 - s experiment (described in Problem 25.45) the...Ch. 25 - * A sinusoidal electromagnetic wave in air has a...Ch. 25 - 48.* EST A microwave oven produces electromagnetic...Ch. 25 - with respect to the axis of the first polarizer....Ch. 25 - BIO Amazing honeybees The survival of a bee colony...Ch. 25 - BIO Amazing honeybees The survival of a bee...Ch. 25 - BIO Amazing honeybees The survival of a bee colony...Ch. 25 - BIO Amazing honeybees The survival of a bee colony...Ch. 25 - BIO Amazing honeybees The survival of a bee colony...Ch. 25 - Incandescent lightbulbs—soon to disappear ...Ch. 25 - BIO Amazing honeybees The survival of a bee colony...Ch. 25 - Incandescent lightbulbssoon to disappear Australia...Ch. 25 - Incandescent lightbulbs—soon to disappear ...Ch. 25 - Incandescent lightbulbs—soon to disappear...
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
- Which of the following is an INCORRECT statement regarding the expanding universe theory? A. Scientists were able to observe that all galaxies and star clusters are moving away from Earth because of the shift of the wavelength to the blue part of the visible spectrum. B. Slipher from 1912 to 1914 studied the electromagnetic radiation of nearby spiral galaxies where he observed that wavelengths of yellow lines appear to be a little orange. C. More recent observation using powerful telescopes confirm that frequency of light from nearby galaxies and star clusters decreases as it is observed here on Earth. D. From the amount of Doppler shift, astronomers are able to compute for the speeds and determine the direction of the motion of nearby galaxies and star clusters.arrow_forward*I really just need to know how to figure out the last question, but I included the first two since the third is based on them* If you observe light emitted from a distance object when the cosmic background temperature was Tz=54K, what is the redshift z of that light? At that redshift, what was the diameter Dz of the universe at that time compared to the diameter of today's universe D0? If you observe an emission line in the spectrum of that object at a wavelength of W nanometers, calculate the rest wavelength of that emission line?arrow_forwardPlease do this carefully.arrow_forward
- Early astronomers thought that galaxies were single stars. Why was this mistake easy to make? A. Galaxies are so far away that they look like a single star. B. Galaxies are made of stars that you can only see one at a time. C. Light from galaxies collects into a single beam. D. Earth is small and galaxies are much larger.arrow_forwardThe age of the universe can be determined if a. the universe is flat. b. the amount of dark matter in the universe can be accurately determined. c. the rate of recession of the galaxies in the Local Group can be accurately determined. d. the temperature of the cosmic background radiation can be accurately determined. e. the Hubble constant and density of the universe can be accurately determined.arrow_forward4arrow_forward
- Please answer in Bold.arrow_forwardB7arrow_forwardThe presence of Dark Matter was theorized due to the curve of the data that the motion of the stars around the central core of our neighboring galaxy (Andromeda) has been approximately flat rather than decreasing at large distances. Which fundamental concept in this chapter helped us in understanding this phenomena? a.) Orbital speed b.) Escape speed c.) Law of equal areas d.) Law of elliptical orbits What happens to the magnitude of the force between two objects with the same mass if we double the distance between them? a.) The magnitude of the force will be doubled. b.) The magnitude of the force will be quadrupled. c.) The magnitude of the force will be halved. d.) The magnitude of the force will be 1/9 of its inital magnitude.e. Earrow_forward
- 3arrow_forwardQuestion A6 The Tully-Fischer method relies on being able to relate the mass of a galaxy to its rotation velocity. Stars in the outer-most regions of the Milky Way galaxy, located at a distance of 50 kpc from the galactic centre, are observed to orbit at a speed Vrot = 250 km s-¹. Using Kepler's 3rd Law, determine the mass in the Milky Way that lies interior to 50 kpc. Express your answer in units of the Solar mass.arrow_forwardQUESTION 6 A galaxy is discovered at a distance of 11 billion light-years from our solar system. We can therefore say: O The galaxy was created within 3 million years after the Big Bang O We are currently observing the galaxy as it existed 11 billion years ago O The galaxy's light is observed at shorter wavelengths than nearby galaxies The galaxy has been 11 billion light-years from our solar system since the Big Bangarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningCollege PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax CollegeHorizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
- University Physics Volume 3PhysicsISBN:9781938168185Author:William Moebs, Jeff SannyPublisher:OpenStaxPhysics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningCollege PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College
Horizons: Exploring the Universe (MindTap Course ...
Physics
ISBN:9781305960961
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
University Physics Volume 3
Physics
ISBN:9781938168185
Author:William Moebs, Jeff Sanny
Publisher:OpenStax
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781305952300
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning