Modern Physics
3rd Edition
ISBN: 9781111794378
Author: Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 16, Problem 11P
To determine
The factor by which the distance between remote galaxies increase in the future.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Assume the observable Universe is charge neutral, and that it contains n nuclei (hydrogen plus helium nuclei, ignoring other elements). Take the helium mass fraction as 1/4. How many electrons are there in the observable Universe? Enter your answer in scientific notation with one decimal place.
Value: n = 4*1080
Question A7
Consider the following line element,
ds² = - dt² + a² (t) (da² + dy²) + b² (t) dz²,
where a(t) and b(t) are distinct functions. State whether or not this line element obeys the
Cosmological Principle, if applied to describe the universe on large scales. Justify your answer.
mathematician Archimedes, responding to a claim that the number of grains of sand was infinite,
calculated that the number of grains of sand needed to fill the universe was on the order of 1063. Our
understanding of the size of the universe has changed since then, and we now know that the
observable universe alone is a sphere with a radius of 1026 m. Estimating the size of a grain of sand,
A) Approximately how many grains of sand would fill the observable universe?
B) How many times larger or smaller is this number than Archimedes' result?
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
- I asked the following question and was given the attached solution: Suppose that the universe were full of spherical objects, each of mass m and radius r . If the objects were distributed uniformly throughout the universe, what number density (#/m3) of spherical objects would be required to make the density equal to the critical density of our Universe? Values: m = 4 kg r = 0.0407 m Answer must be in scientific notation and include zero decimal places (1 sig fig --- e.g., 1234 should be written as 1*10^3) I don't follow the work and I got the wrong answer, so please help and show your work as I do not follow along easily thanksarrow_forwardAn astronomer observed the motions of some galaxies. Based on his observations, he made the following statements. Which one of them is most likely to be false? Take Hubble's constant to be 67 km/s/Mpc. A. A galaxy observed to be moving away from us at a speed of 70 km/s is at a distance of about 1 Mpc from us. B. A galaxy observed to be moving away from us at a speed of 700 km/s is at a distance of about 10 Mpc from us. C. A galaxy observed to be moving away from us at a speed of 7000 km/s is at a distance of about 100 Mpc from us. D. A galaxy observed to be moving away from us at a speed of 70000 km/s is at a distance of about 1 Gpc from us. Is the answer D? Thank you!arrow_forwardSuppose that the universe were full of spherical objects, each of mass m and radius r . If the objects were distributed uniformly throughout the universe, what number density (#/m3) of spherical objects would be required to make the density equal to the critical density of our Universe? Values: m = 10 kg r = 0.0399 m Answer must be in scientific notation and include zero decimal places (1 sig fig --- e.g., 1234 should be written as 1*10^3)arrow_forward
- 1. The current (critical) density of our universe is pe = 10-26kg/m³. Assume the universe is filled with cubes with equal size that each contain one person of m = 100kg. What would the length of the side of such a cube have to be in order to give the correct critical density? How many hydrogen atoms would you need in a box of 1 m³ to reach the critical density? The matter we know, which consists mostly of hydrogen, constitutes only 4.8% of the current critical energy density of our universe. So how many hydrogen atoms are actually in a box of 1 m3 in our universe? Deep space is very empty and a much better vacuum than we can obtain on earth in a laboratory.arrow_forwardAssuming that hydrogen fusion requires the Universe to have a temperature of T > 10' K (as measured by the CMB), determine the redshift at which the fusion of hydrogen into helium was just possible as the Universe expanded and cooled. Choose the option below that most closely matches your answer. Select one: Оа. 4000.87 b. 3669723.77 О с 2229723.71 O d. 9748293.14 O e. 4669723.16arrow_forwardAsap please....arrow_forward
- The matter density in the Universe today is Pm = -27 kg m-3. What would 2.7 x 10 be the value of the density parameter, 2o, if the Hubble constant had the value Ho = 38 km/s/Mpc? Assume the Universe does not contain dark energy and choose the option below that best matches your answer. Select one: O a. 0.1 O b. 2. О с. 1. O d. 0.7 О е. 0.5arrow_forwardA galaxy is observed to recede from Earth with an approximate speed of 0.81c. Approximately how far d from Earth is this galaxy? Give an answer in units of megaparsecs (Mpc). d = ? Mpc How long ago t was the light that we see emitted by the galaxy? Give an answer in units of years. t = ? yearsarrow_forwardIf a galaxy is 9.0 Mpc away from Earth and recedes at 488 km/s, what is H0 (in km/s/Mpc)? km/s/Mpc What is the Hubble time (in yr)? years How old (in yr) would the universe be, assuming space-time is flat and the expansion of the universe has not been accelerating? How would acceleration change your answer? A.If the expansion of the Universe has been accelerating, the Universe could be substantially younger than the value entered above. BIf the expansion of the Universe has been accelerating, the Universe could be substantially older than the value entered above.arrow_forward
- Consider the following line element, ds² = -dt² + a² (t) (dx² + dy²) + b²(t) dz², where a(t) and b(t) are distinct functions. State whether or not this line element obeys the Cosmological Principle, if applied to describe the universe on large scales. Justify your answer.arrow_forwardWhy can't we see past the cosmological horizon? The universe extends only to this horizon. Beyond the cosmological horizon, the Universe curves away from us, like the surface of the Earth. O We do not have telescopes big enough. Beyond the cosmological horizon, we are looking back to a time before the universe had formed.arrow_forwardCalculation of the gravitational force.1. What is the gravitational force (in N) on a proton at the surface of the Sun?2. At a point mid way to the surface? The average density ρ of the Universe today is 3 × 10−27kgm−3 Find this density in (a) gcm^−3(b) M⊙Mpc^−3(c) mpcm^−32. Find the mass within a sphere of radius (a) R⊙ (b) 1 AU (c) 10 Mparrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Modern PhysicsPhysicsISBN:9781111794378Author:Raymond A. Serway, Clement J. Moses, Curt A. MoyerPublisher:Cengage LearningPhysics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
- University Physics Volume 3PhysicsISBN:9781938168185Author:William Moebs, Jeff SannyPublisher:OpenStaxPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
Modern Physics
Physics
ISBN:9781111794378
Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher:Cengage Learning
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
University Physics Volume 3
Physics
ISBN:9781938168185
Author:William Moebs, Jeff Sanny
Publisher:OpenStax
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
Astronomy
Physics
ISBN:9781938168284
Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff
Publisher:OpenStax