EP PHYSICS F/SCI.+ENGR.W/MOD..-MOD MAST
4th Edition
ISBN: 9780133899634
Author: GIANCOLI
Publisher: PEARSON CO
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 44, Problem 20Q
(a)
To determine
The reason for type Ia supernovae being so useful for determining the distances of galaxies.
(b)
To determine
The way in which the distances between galaxies is actually measured by type Ia supernovae.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
The visible section of the Universe is a sphere centered on the bridge of your nose, with radius 13.7 billion light-years. (a) Explain why the visible Universe is getting larger, with its radius increasing by one light-year in every year. (b) Find the rate at which the volume of the visible section of the Universe is increasing.
To get an idea of how empty deep space is on the average, perform the following calculations:
(a) Find the volume our Sun would occupy if it had an average density equal to the critical density of 10-26 kg / m3 thought necessary to halt the expansion of the universe.
(b) Find the radius of a sphere of this volume in light years.
(c) What would this radius be if the density were that of luminous matter, which is approximately 5% that of the critical density?
(d) Compare the radius found in part (c) with the 4-ly average separation of stars in the arms of the Milky Way.
Distances to very remote galaxies are estimated based on their apparent type, which indicate the number of stars in thegalaxy, and their measured brightness. Explain how the measured brightness would vary with distance. Would there be anycorrection necessary to compensate for the red shift of the galaxy (all distant galaxies have significant red shifts)? Discusspossible causes of uncertainties in these measurements
Chapter 44 Solutions
EP PHYSICS F/SCI.+ENGR.W/MOD..-MOD MAST
Ch. 44.1 - Suppose we could place a huge mirror 1 light-year...Ch. 44.2 - Prob. 1BECh. 44.4 - What is the Schwarzschild radius for an object...Ch. 44.4 - A black hole has radius R. Its mass is...Ch. 44.9 - Prob. 1EECh. 44 - The Milky Way was once thought to be murky or...Ch. 44 - Prob. 2QCh. 44 - Prob. 3QCh. 44 - Prob. 4QCh. 44 - Prob. 5Q
Ch. 44 - Prob. 6QCh. 44 - Prob. 7QCh. 44 - Prob. 8QCh. 44 - Prob. 9QCh. 44 - Prob. 10QCh. 44 - Prob. 11QCh. 44 - Prob. 12QCh. 44 - Prob. 13QCh. 44 - Compare an explosion on Earth to the Big Bang....Ch. 44 - If nothing, not even light, escapes from a black...Ch. 44 - Prob. 16QCh. 44 - Prob. 17QCh. 44 - Explain what the 2.7-K cosmic microwave background...Ch. 44 - Prob. 19QCh. 44 - Prob. 20QCh. 44 - Prob. 21QCh. 44 - Under what circumstances would the universe...Ch. 44 - Prob. 23QCh. 44 - Prob. 24QCh. 44 - Prob. 1PCh. 44 - Prob. 2PCh. 44 - Prob. 3PCh. 44 - Prob. 4PCh. 44 - Prob. 5PCh. 44 - Prob. 6PCh. 44 - (II) What is the relative brightness of the Sun as...Ch. 44 - Prob. 8PCh. 44 - Prob. 9PCh. 44 - Prob. 10PCh. 44 - Prob. 11PCh. 44 - Prob. 12PCh. 44 - Prob. 13PCh. 44 - Prob. 14PCh. 44 - Prob. 15PCh. 44 - Prob. 16PCh. 44 - Prob. 17PCh. 44 - Prob. 18PCh. 44 - Prob. 19PCh. 44 - Prob. 20PCh. 44 - Prob. 21PCh. 44 - Prob. 22PCh. 44 - Prob. 23PCh. 44 - Prob. 24PCh. 44 - Prob. 25PCh. 44 - Prob. 26PCh. 44 - Prob. 27PCh. 44 - Prob. 28PCh. 44 - Prob. 29PCh. 44 - Prob. 30PCh. 44 - Prob. 31PCh. 44 - (II) Calculate the peak wavelength of the CMB at...Ch. 44 - Prob. 33PCh. 44 - (II) The scale factor or the universe (average...Ch. 44 - Prob. 35PCh. 44 - Prob. 36PCh. 44 - Prob. 37GPCh. 44 - Prob. 38GPCh. 44 - Prob. 39GPCh. 44 - Prob. 40GPCh. 44 - Prob. 41GPCh. 44 - Prob. 42GPCh. 44 - Prob. 43GPCh. 44 - Prob. 44GPCh. 44 - Prob. 45GPCh. 44 - Prob. 46GPCh. 44 - Prob. 47GPCh. 44 - Prob. 48GPCh. 44 - Prob. 49GPCh. 44 - Prob. 50GPCh. 44 - Calculate the Schwarzschild radius using a...Ch. 44 - How large would the Sun be if its density equaled...Ch. 44 - Prob. 53GPCh. 44 - (a) Use special relativity and Newtons law of...Ch. 44 - Prob. 55GPCh. 44 - Prob. 56GPCh. 44 - Prob. 57GPCh. 44 - Prob. 58GP
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
- Approximate values of length (in meters) 107 Diameter of Earth 1011 Distance from Earth to Sun 1016 Distance traveled by light in one year 1021 Diameter of the Milky Way Galaxy 1022 Distance from Earth to the nearest galaxy 1025 Distance from Earth to the edge of the known universearrow_forwardIt can be shown that if an object orbiting a star of mass M in a circular orbit of radius R has speed v, then Rv? M Suppose a star orbits the center of the galaxy it is contained in with an orbit that is nearly circular with radius 18 R = 2.5 x 10 and velocity v = 230 km/s. Use the result above to estimate the mass of the portion of the galaxy inside the star's orbit (place all of this mass at the center of the orbit). Mass =arrow_forwardAnother commonly calculated velocity in galactic dynamics is the escape velocity vesc, that is the minimum velocity a star must have in order to escape the gravitational field of the galaxy. (a) Starting from the work required to move a body over a distance dr against f show that the escape velocity from a point mass galaxy is vsc = 2GM/r where r is your initial distance. (b) Since we know galaxies aren't actually point-masses, also show that vesc from r for a galaxy with a p(r) xr¯² density profile is vese that R is a cutoff radius at which the mass density is zero. = 2v(1+ ln(R/r)). Here you must assume (c) The largest velocity measured for any star in the solar neighbourhood, at r=8 kpc, is 440 km/s. Assuming that this star is still bound to the galaxy, find the lower limit (in kiloparsecs), to the cutoff radius R and a lower limit (in solar units) to the mass of the galaxy. Note the solar rotation velocity is 220 km/s.arrow_forward
- Distribution of Dark matter The most mass of our Milky Way is contained in an inner region close to the core with radius R0.Because the mass outside this inner region is almost constant, the density distribution can bewritten as following (assume a flat Milky Way with height z0):ρ(r) = (ρ0, r ≤ R00, r > R0(a) Derive an expression for the mass M(r) enclosed within the radius r.(b) Derive the expected rotational velocity of the Milky Way v(r) at a radius r.arrow_forwardIn vacuum, the H-alpha line has a rest-frame wavelength of 656.461 nm. You took a spectrum of the center of a galaxy at an observatory on the ground and measured a wavelength of 656.65 nm for the H-alpha line. What is the radial velocity of the galaxy relative to the observer [km/s]? Note that the index of refraction of air is 1.0003 at that wavelength. As a result, the rest-frame wavelength of the H-alpha line in air differs from the rest-frame wavelength in vacuum.arrow_forwardAnother commonly calculated velocity in galactic dynamics is the escape velocity vesc, that is the minimum velocity a star must have in order to escape the gravitational field of the galaxy. (a) Starting from the work required to move a body over a distance dr against f show that the escape velocity from a point mass galaxy is vse = 2GM/r where r is your initial distance. (b) Since we know galaxies aren't actually point-masses, also show that vesc from r for a galaxy with a p(r) x r-² density profile is vse = 2v²(1+ ln(R/r)). Here you must assume that R is a cutoff radius at which the mass density is zero. (c) The largest velocity measured for any star in the solar neighbourhood, at r=8 kpc, is 440 km/s. Assuming that this star is still bound to the galaxy, find the lower limit (in kiloparsecs), to the cutoff radius R and a lower limit (in solar units) to the mass of the galaxy. Note the solar rotation velocity is 220 km/s.arrow_forward
- The most distant quasar is "J0313-1806". Its redshift is z = 7.64. [ z = (femitted - fobserved)/ fobserved] Assume that the redshift is due to relative motion. Then how fast is the quasar moving away from Earth? (speed as the fraction of c = ) | .704 According to Hubble's Law, the distance (r) depends on the speed of recession (v) according to v = Hor where Ho~ 20km/s Mly How many years are required for light to travel from the quasar to Earth? (years = )arrow_forwardWhen two galaxies collide, the stars inside them are not likely to be much affected, because the __________ stars is so large compared to their diameters. However, the _______ of stars and gas can be changed, altering the appearance of the galaxies. Astronomers have determined that such collisions are seen more often in ____________. When two galaxies of roughly equal size collide, astronomers call it a _______ of galaxies; but when a small galaxy collides with a much larger one, the process is called ___________. When a galaxy has a significant amount of its interstellar gas compressed by a collision, leading to the birth of many new stars, astronomers call it a __________ galaxy.arrow_forwardSuppose that a galaxy has 109 M⊙ of neutral HI gas with a temperature of about 10 K. Estimate the luminosity of the 21 cm wavelength radiation that is expected from the galaxy. Answer in watts.arrow_forward
- An observational survey of distant galaxies is undertaken that involves measuring their distances using cepheid variables and red-shifts using spectroscopy. Explain how cepheid variables can be used to measure the distances to galaxies. A spectral line is observed whose wavelength in the laboratory is de length of this spectral line observed in each galaxy, Xo, is listed in the table, along with the distance, d, to the galaxy. Determine the red-shift and the recession velocity of each galaxy and tabulate your results by making a copy of the table and filling in the blank spaces. Sketch a Hubble diagram using your results and determine the value of the Hubble constant Ho in units of km s-1 Mpc. 650 nm. The wave- Galaxy 1 652.69 Galaxy 2 Galaxy 3 Galaxy 4 Galaxy 5 653.01 do (nm) d (Mpc) 658.54 662.18 681.63 17 19 54 77 200 v (km s-1)arrow_forwardOne of the strongest emission lines observed from distant galaxies comes from hydrogen and has a wavelength of 122 nm (in the ultraviolet region). How fast must a galaxy be moving away from us in order for that line to be observed in the visible region at 366 nm?arrow_forwarda) Define the term “standard candle” as used in cosmology b). The flux is defined as f(Dlum) = L /4πD2lum , where L is the absolute luminosity and Dlum is the distance to the radiation source (you may assume z ≪ 1). Assume that we have measured the flux to be f = 7.234 10−23Wm−2 and the absolute luminosity is given by L = 3.828 1026W. Calculate the luminosity distance Dlum to the object in Mpc. c). Calculate the distance modulus µ for the object of the previous subquestion. Show that the distance modulus µ can be written as given in imagearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
AstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
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
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning