Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Question
Chapter 21, Problem 12Q
To determine
(a)
To calculate:
The radius and diameter of the Crab Nebula, if expanding gas is moving at the speed of 1450 m/s since the year in which it was observed.
To determine
(b)
To compare:
The result obtained in part (a) to the actual size of the nebula.
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A planetary nebula expanded in radius 0.3 arc seconds in 30 years. Doppler measurements show the nebula is expanding at a rate of 35 km/s. How far away is the nebula in parsecs?
First, determine what distance the nebular expanded in parsecs during the time mentioned. Δd = vpc/sTs
So we first need to convert the rate into pc/s and the time into seconds:
vpc/s = vkm/s (1 pc / 3.09 x 1013km)
vpc/s = ?
Ts = (Tyr)(365 days/yr)(24 hrs/day)(3600 s/hr)
Ts = ? s
Δd= vpc/sTs
Therefore, Δd = ? pc
Assuming that at the end of the He burning phase of the stellar core (r < R_core) has no H or He or other metals and is composed completely of Carbon, X=Y=0, X_c = 1 ; The envelope above the core has a normal stellar composition ( r > R_core). Calculate the length of time in years that a 1M_sol and 10M_sol star will live on the horizontal branch or the time between the start and end of the He burning phase. Assume that the normal relationship between mass and luminosity holds for horizontal branch stars. Please be as detailed as possible
Place the following events in the formation of stars in the proper chronological
sequence, with the oldest first and the youngest last.
w. the gas and dust in the nebula flatten to a disk shape due to gravity
and a steadily increasing rate of angular rotation
x. a star emerges when the mass is great enough and the temperature is
high enough to trigger thermonuclear fusion in the core
y. the rotation of the nebular cloud increases as gas and dust
concentrates by gravity within the growing protostar in the center
z. some force, perhaps from a nearby supernova, imparts a rotation to a
nebular cloud
y, then z, then w, then x
z, then y, then w, then x
w, then y, then z, then x
z, then x, then w, then y
x, then z, then y, then w
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Chapter 21 Solutions
Universe: Stars And Galaxies
Ch. 21 - Prob. 1QCh. 21 - Prob. 2QCh. 21 - Prob. 3QCh. 21 - Prob. 4QCh. 21 - Prob. 5QCh. 21 - Prob. 6QCh. 21 - Prob. 7QCh. 21 - Prob. 8QCh. 21 - Prob. 9QCh. 21 - Prob. 10Q
Ch. 21 - Prob. 11QCh. 21 - Prob. 12QCh. 21 - Prob. 13QCh. 21 - Prob. 14QCh. 21 - Prob. 15QCh. 21 - Prob. 16QCh. 21 - Prob. 17QCh. 21 - Prob. 18QCh. 21 - Prob. 19QCh. 21 - Prob. 20QCh. 21 - Prob. 21QCh. 21 - Prob. 22QCh. 21 - Prob. 23QCh. 21 - Prob. 24QCh. 21 - Prob. 25QCh. 21 - Prob. 26QCh. 21 - Prob. 27QCh. 21 - Prob. 28QCh. 21 - Prob. 29QCh. 21 - Prob. 30QCh. 21 - Prob. 31QCh. 21 - Prob. 32QCh. 21 - Prob. 33QCh. 21 - Prob. 34QCh. 21 - Prob. 35QCh. 21 - Prob. 36QCh. 21 - Prob. 37QCh. 21 - Prob. 38QCh. 21 - Prob. 39QCh. 21 - Prob. 40QCh. 21 - Prob. 41QCh. 21 - Prob. 42QCh. 21 - Prob. 43QCh. 21 - Prob. 44QCh. 21 - Prob. 45QCh. 21 - Prob. 46QCh. 21 - Prob. 47QCh. 21 - Prob. 48QCh. 21 - Prob. 49QCh. 21 - Prob. 50QCh. 21 - Prob. 51QCh. 21 - Prob. 52QCh. 21 - Prob. 53QCh. 21 - Prob. 54QCh. 21 - Prob. 55QCh. 21 - Prob. 56QCh. 21 - Prob. 57QCh. 21 - Prob. 58QCh. 21 - Prob. 59QCh. 21 - Prob. 60QCh. 21 - Prob. 61QCh. 21 - Prob. 62QCh. 21 - Prob. 63QCh. 21 - Prob. 64QCh. 21 - Prob. 65QCh. 21 - Prob. 66QCh. 21 - Prob. 67QCh. 21 - Prob. 68QCh. 21 - Prob. 69QCh. 21 - Prob. 70QCh. 21 - Prob. 71QCh. 21 - Prob. 72QCh. 21 - Prob. 73QCh. 21 - Prob. 74QCh. 21 - Prob. 75Q
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