College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 34, Problem 16PE
Show that the velocity of a star orbiting its galaxy in a circular orbit is inversely proportional to the square root of its orbital radius, assuming the mass of the stars inside its orbit acts like a single mass at the center of the galaxy. You may use an equation from a previous chapter to support your conclusion, but you must justify its use and define all terms used.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
ROTATIONAL DYNAMICS
Question 01
A solid circular cylinder and a solid spherical ball of the same mass and radius are rolling
together down the same inclined. Calculate the ratio of their kinetic energy. Assume pure
rolling motion Question 02
A sphere and cylinder of the same mass and radius start from ret at the same point and more
down the same plane inclined at 30° to the horizontal
Which body gets the bottom first and what is its acceleration
b) What angle of inclination of the plane is needed to give the slower body the same
acceleration
Question 03
i)
Define the angular velocity of a rotating body and give its SI unit
A car wheel has its angular velocity changing from 2rads to 30 rads
seconds. If the radius of the wheel is 400mm. calculate
ii)
The angular acceleration
iii)
The tangential linear acceleration of a point on the rim of the wheel
Question 04
in 20
Question B3
Consider the following FLRW spacetime:
t2
ds² = -dt² +
(dx²
+ dy²+ dz²),
t2
where t is a constant.
a)
State whether this universe is spatially open, closed or flat.
[2 marks]
b) Determine the Hubble factor H(t), and represent it in a (roughly drawn) plot as a function
of time t, starting at t = 0.
[3 marks]
c) Taking galaxy A to be located at (x, y, z) = (0,0,0), determine the proper distance to galaxy
B located at (x, y, z) = (L, 0, 0). Determine the recessional velocity of galaxy B with respect
to galaxy A.
d) The Friedmann equations are
2
k
8πG
а
4πG
+
a²
(p+3p).
3
a
3
[5 marks]
Use these equations to determine the energy density p(t) and the pressure p(t) for the
FLRW spacetime specified at the top of the page.
[5 marks]
e) Given the result of question B3.d, state whether the FLRW universe in question is (i)
radiation-dominated, (ii) matter-dominated, (iii) cosmological-constant-dominated, or (iv)
none of the previous. Justify your answer.
f)
[5 marks]
A conformally…
SECTION B
Answer ONLY TWO questions in Section B
[Expect to use one single-sided A4 page for each Section-B sub question.]
Question B1
Consider the line element
where w is a constant.
ds²=-dt²+e2wt dx²,
a) Determine the components of the metric and of the inverse metric.
[2 marks]
b) Determine the Christoffel symbols. [See the Appendix of this document.]
[10 marks]
c)
Write down the geodesic equations.
[5 marks]
d) Show that e2wt it is a constant of geodesic motion.
[4 marks]
e)
Solve the geodesic equations for null geodesics.
[4 marks]
Chapter 34 Solutions
College Physics
Ch. 34 - Explain why it only appears that we are at the...Ch. 34 - If there is no observable edge to the universe,...Ch. 34 - If the universe is infinite, does it have a...Ch. 34 - Another known cause of red shift in light is the...Ch. 34 - If some unknown cause of red shiftsuch as light...Ch. 34 - Olbers’s paradox poses an interesting question: If...Ch. 34 - If the cosmic microwave background radiation...Ch. 34 - The decay of one type of Kmeson is cited as...Ch. 34 - Distances to local galaxies are determined by...Ch. 34 - Distances to very remote galaxies are estimated...
Ch. 34 - If the smallest meaningful time interval is...Ch. 34 - Quantum gravity, if developed, would be an...Ch. 34 - Does observed gravitational lensing correspond to...Ch. 34 - Suppose you measure the red shifts of all the...Ch. 34 - What are gravitational waves, and have they yet...Ch. 34 - Is the event horizon of a black hole the actual...Ch. 34 - Suppose black holes radiate their mass away and...Ch. 34 - Discuss the possibility that star velocities at...Ch. 34 - How does relativistic time dilation prohibit...Ch. 34 - If neutrino oscillations do occur, will they...Ch. 34 - Lacking direct evidence of WIMPs as dark matter,...Ch. 34 - Must a complex system be adaptive to be of...Ch. 34 - State a necessary condition for a System to be...Ch. 34 - What is critical temperature Tc? Do all materials...Ch. 34 - Explain how good thermal contact with liquid...Ch. 34 - Not only is liquid nitrogen a cheaper coolant than...Ch. 34 - For experimental evidence particularly of...Ch. 34 - Discuss whether you think there are limits to what...Ch. 34 - Find the approximate mass of the luminous matter...Ch. 34 - Find the approximate mass of the dark and luminous...Ch. 34 - (a) Estimate the mass of the luminous matter in...Ch. 34 - If a galaxy is 500 Mly away from us, how fast do...Ch. 34 - On average, how far away are galaxies mat are...Ch. 34 - Our solar system orbits the center of the Milky...Ch. 34 - (a) What is the approximate speed relative to us...Ch. 34 - (a) Calculate The approximate age of the universe...Ch. 34 - Assuming a circular orbit for the Sun about the...Ch. 34 - (a) What is the approximate force of gravity on a...Ch. 34 - Andromeda galaxy is the closest large galaxy and...Ch. 34 - (a) A particle and its antiparticle are at rest...Ch. 34 - The average particle energy needed to observe...Ch. 34 - The peak intensity of the CMBR occurs at a...Ch. 34 - (a) What Hubble constant corresponds to an...Ch. 34 - Show that the velocity of a star orbiting its...Ch. 34 - The core of a star collapses during a supernova,...Ch. 34 - Using data from the previous problem, find the...Ch. 34 - Distances to the nearest stars (up to 500 by away)...Ch. 34 - (a) Use the Heisenberg uncertainty principle to...Ch. 34 - Construct Your Own Problem Consider a star moving...Ch. 34 - What is the Schwarzschild radius of a blank hole...Ch. 34 - Black holes with masses smaller than muse formed...Ch. 34 - Supermassive black holes are thought to exist at...Ch. 34 - Construct Your Own Problem Consider a supermassive...Ch. 34 - The characteristic length of entities in...Ch. 34 - If the dark matter in the Milky Way were composed...Ch. 34 - The critical mass density needed to just halt the...Ch. 34 - Assume the average density of the universe is 0.1...Ch. 34 - To get an idea of how empty deep spam is on the...Ch. 34 - A section of superconducting wire carries a...
Additional Science Textbook Solutions
Find more solutions based on key concepts
2. Julie drives 100 mi to Grandmother’s house. On the way to Grandmother’s, Julie drives half the distance at 4...
Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
1. An object is subject to two forces that do not point in opposite directions. Is it possible to choose their ...
College Physics: A Strategic Approach (3rd Edition)
Raw Oysters and Antacids: A Deadly Mix? The highly acidic environment of the stomach kills most bacteria before...
Microbiology with Diseases by Body System (5th Edition)
Match the following cell types with their correct definition. _________Macrophage _________NK cell _________Eos...
Human Anatomy & Physiology (2nd Edition)
Some organizations are starting to envision a sustainable societyone in which each generation inherits sufficie...
Campbell Essential Biology (7th Edition)
2. Whether an allele is dominant or recessive depends on
a. how common the allele is, relative to other alleles...
Campbell Biology: Concepts & Connections (9th Edition)
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
- Page 2 SECTION A Answer ALL questions in Section A [Expect to use one single-sided A4 page for each Section-A sub question.] Question A1 SPA6308 (2024) Consider Minkowski spacetime in Cartesian coordinates th = (t, x, y, z), such that ds² = dt² + dx² + dy² + dz². (a) Consider the vector with components V" = (1,-1,0,0). Determine V and V. V. (b) Consider now the coordinate system x' (u, v, y, z) such that u =t-x, v=t+x. [2 marks] Write down the line element, the metric, the Christoffel symbols and the Riemann curvature tensor in the new coordinates. [See the Appendix of this document.] [5 marks] (c) Determine V", that is, write the object in question A1.a in the coordinate system x'. Verify explicitly that V. V is invariant under the coordinate transformation. Question A2 [5 marks] Suppose that A, is a covector field, and consider the object Fv=AAμ. (a) Show explicitly that F is a tensor, that is, show that it transforms appropriately under a coordinate transformation. [5 marks] (b)…arrow_forwardHow does boiling point of water decreases as the altitude increases?arrow_forwardNo chatgpt pls will upvotearrow_forward
- 14 Z In figure, a closed surface with q=b= 0.4m/ C = 0.6m if the left edge of the closed surface at position X=a, if E is non-uniform and is given by € = (3 + 2x²) ŷ N/C, calculate the (3+2x²) net electric flux leaving the closed surface.arrow_forwardNo chatgpt pls will upvotearrow_forwardsuggest a reason ultrasound cleaning is better than cleaning by hand?arrow_forward
- Checkpoint 4 The figure shows four orientations of an electric di- pole in an external electric field. Rank the orienta- tions according to (a) the magnitude of the torque on the dipole and (b) the potential energy of the di- pole, greatest first. (1) (2) E (4)arrow_forwardWhat is integrated science. What is fractional distillation What is simple distillationarrow_forward19:39 · C Chegg 1 69% ✓ The compound beam is fixed at Ę and supported by rollers at A and B. There are pins at C and D. Take F=1700 lb. (Figure 1) Figure 800 lb ||-5- F 600 lb بتا D E C BO 10 ft 5 ft 4 ft-—— 6 ft — 5 ft- Solved Part A The compound beam is fixed at E and... Hình ảnh có thể có bản quyền. Tìm hiểu thêm Problem A-12 % Chia sẻ kip 800 lb Truy cập ) D Lưu of C 600 lb |-sa+ 10ft 5ft 4ft6ft D E 5 ft- Trying Cheaa Những kết quả này có hữu ích không? There are pins at C and D To F-1200 Egue!) Chegg Solved The compound b... Có Không ☑ ||| Chegg 10 וחarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
College PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning
University Physics Volume 3PhysicsISBN:9781938168185Author:William Moebs, Jeff SannyPublisher:OpenStax
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage Learning
College Physics
Physics
ISBN:9781305952300
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
University Physics Volume 3
Physics
ISBN:9781938168185
Author:William Moebs, Jeff Sanny
Publisher:OpenStax
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Stars and Galaxies (MindTap Course List)
Physics
ISBN:9781337399944
Author:Michael A. Seeds
Publisher:Cengage Learning