21st Century Astronomy (sixth Edition)
6th Edition
ISBN: 9780393675504
Author: Laura Kay, Stacy Palen, George Blumenthal
Publisher: W. W. Norton & Company
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 16, Problem 25QP
To determine
The prediction about the star.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A red giant star might have radius = 104 times the solar radius,
and luminosity = 1730 times solar luminosity.
Use the data given below to calculate the temperature
at the surface of the red giant star.
Data:
solar radius R = 7 x 108 meters
solar luminosity L = 4 x 1026 watts
Stefan-Boltzmann constant
a = 5.67 x 10-8 W m² K-4
(in K)
A: 1226 OB: 1434 OC: 1678 OD: 1963 OE: 2297 OF: 2688 OG: 3145 OH: 3679
The mass-luminosity relation describes the mathematical relationship between luminosity and mass for main sequence stars. It describes how a star with a mass of 4 M⊙ would have a luminosity of ______ L⊙.
If a star has a radius 1/2 that of the Sun and a temperature 4 that of the Sun, how many times higher is the star's luminosity than that of the Sun? (If it is smaller by a factor of 8, you would write 0.125 because 1/8=0.125)
If a star has a radius 2 times larger than the Sun's and a luminosity 1/4th that of the Sun, how many times higher is the star's temperature than that of the Sun? (If it is smaller by a factor of 8, you would write 0.125 because 1/8=0.125)
If a star has a surface temperature 2 times lower than the Sun's and a luminosity the same as the Sun, how many times larger is the star than the Sun? (If it is smaller by a factor of 8, you would write 0.125 because 1/8=0.125)
For the PP chain 0.7% of the mass participating in nuclear fusion is liberated as energy which
produces a star's luminosity. Assume that the core of a main sequence star consists of 10% of its
total mass. Hence, estimate the lifetime of a star on the main sequence in terms of its luminosity
L/L. Give your answer in years. You may use the observed mass-luminosity relation L x M³.5,
where M is the star's total mass.
Using typical values, calculate estimates for the main sequence lifetime of a KO star and a 05
star. Describe briefly why your estimate might be more accurate for K stars compared to O stars.
Chapter 16 Solutions
21st Century Astronomy (sixth Edition)
Ch. 16.1 - Prob. 16.1CYUCh. 16.3 - Prob. 16.3CYUCh. 16.4 - Prob. 16.4CYUCh. 16.5 - Prob. 16.5CYUCh. 16 - Prob. 1QPCh. 16 - Prob. 2QPCh. 16 - Prob. 3QPCh. 16 - Prob. 4QPCh. 16 - Prob. 5QPCh. 16 - Prob. 6QP
Ch. 16 - Prob. 8QPCh. 16 - Prob. 9QPCh. 16 - Prob. 10QPCh. 16 - Prob. 11QPCh. 16 - Prob. 12QPCh. 16 - Prob. 13QPCh. 16 - Prob. 14QPCh. 16 - Prob. 15QPCh. 16 - Prob. 16QPCh. 16 - Prob. 17QPCh. 16 - Prob. 18QPCh. 16 - Prob. 19QPCh. 16 - Prob. 20QPCh. 16 - Prob. 21QPCh. 16 - Prob. 23QPCh. 16 - Prob. 24QPCh. 16 - Prob. 25QPCh. 16 - Prob. 26QPCh. 16 - Prob. 27QPCh. 16 - Prob. 28QPCh. 16 - Prob. 29QPCh. 16 - Prob. 30QPCh. 16 - Prob. 31QPCh. 16 - Prob. 32QPCh. 16 - Prob. 33QPCh. 16 - Prob. 34QPCh. 16 - Prob. 35QPCh. 16 - Prob. 36QPCh. 16 - Prob. 37QPCh. 16 - Prob. 38QPCh. 16 - Prob. 39QPCh. 16 - Prob. 40QPCh. 16 - Prob. 41QPCh. 16 - Prob. 42QPCh. 16 - Prob. 43QPCh. 16 - Prob. 44QPCh. 16 - Prob. 45QP
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
- Describe the evolution of a star with a mass similar to that of the Sun, from the protostar stage to the time it first becomes a red giant. Give the description in words and then sketch the evolution on an HR diagram.arrow_forwardAccording to the text, a star must be hotter than about 25,000 K to produce an H II region. Both the hottest white dwarfs and main-sequence O stars have temperatures hotter than 25,000 K. Which type of star can ionize more hydrogen? Why?arrow_forwardThe text says a star does not change its mass very much during the course of its main-sequence lifetime. While it is on the main sequence, a star converts about 10% of the hydrogen initially present into helium (remember it’s only the core of the star that is hot enough for fusion). Look in earlier chapters to find out what percentage of the hydrogen mass involved in fusion is lost because it is converted to energy. By how much does the mass of the whole star change as a result of fusion? Were we correct to say that the mass of a star does not change significantly while it is on the main sequence?arrow_forward
- Which of the following can you determine about a star without knowing its distance, and which can you not determine: radial velocity, temperature, apparent brightness, or luminosity? Explain.arrow_forwardIf a 3 and 8 MSunstar formed together in a binary system, which star would: A. Evolve off the main sequence first? B. Form a carbon- and oxygen-rich white dwarf? C. Be the location for a nova explosion?arrow_forwardHow do stars typically “move” through the main sequence band on an HR diagram? Why?arrow_forward
- Observations show that stellar luminosity, L, and mass, M, are related by L x M3.5 for main sequence stars. Obtain an expression that relates the main sequence life time and the mass of a star. You should assume that the luminosity is constant throughout a star's main sequence life time, and that the amount of mass converted into energy by a star while it is on the main sequence is given by AM main sequence life time of a 20 Solar mass star given that the Sun is expected to spend 1010 years on the main sequence. Comment on the significance of your answer. fM, where f is a constant. Estimate thearrow_forwardFor a main sequence star with luminosity L, how many kilograms of hydrogen is being converted into helium per second? Use the formula that you derive to estimate the mass of hydrogen atoms that are converted into helium in the interior of the sun (LSun = 3.9 x 1026 W). (Note: the mass of a hydrogen atom is 1 mproton and the mass of a helium atom is 3.97 mproton. You need four hydrogen nuclei to form one helium nucleus.)arrow_forwardIn the H-R diagram we see that stellar masses__________ downward along the main sequence. At the upper end of the main sequence, the hot, luminous O stars can have masses as high as _________ or more times that of the Sun. On the lower end, cool, dim M stars may have as little as __________ times the mass of the Sun. Many more stars fall on the lower end of the main sequence than on the upper end, which tells us that _________stars are much more common than __________ stars.arrow_forward
- Using solar units, we find that a star has 4 times the luminosity of the Sun, a mass 1.25 times the mass of the Sun, and a surface temperature of 4090 K (take the Sun's surface temperature to be 5784 K for the sake of this problem). This means the star has a radius of.................... solar radii and is a .................... star (use the classification).arrow_forwardA star with spectral type A0 has a surface temperature of 9600 K and a radius of 2.2 RSun. How many times more luminous is this star than the Sun? (if it is less luminous enter a number less than one) This star has a mass of 3.3 MSun. Using the simple approximation that we made in class, what is the main sequence lifetime of this star? You may assume that the lifetime of the sun is 1010 yr. Compare this to the lifetime of a A0 star listed in Table 22.1 (computed using a more sophisticated approach). Is the value you calculated in the previous problem longer or shorter than what is reported in the table? (L for longer, S for shorter) (You only get one try at this problem.)arrow_forwardFor each statement concerning main sequence stars, select T True, F False, G Greater than, L Less than, or E Equal to. A) The surface temperature of a O type star is .... than a K type star. B) On the main sequence, the mass of a O type star is .... than a F type star. C) On the main sequence, a M type star's life is .... than a G type star. D) The surface temperature of our Sun is .... than the surface temperature of Sirius. E) When stars start hydrogen burning, thier mass determines where they are on the main sequence. F) Based on the relative lifes of M and G type stars we expect the number of M stars to be .... than the number of G type stars.arrow_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
Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher: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
Foundations of Astronomy (MindTap Course List)
Physics
ISBN:9781337399920
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning
Stars and Galaxies
Physics
ISBN:9781305120785
Author:Michael A. Seeds, Dana Backman
Publisher:Cengage Learning