Foundations of Astronomy (MindTap Course List)
14th Edition
ISBN: 9781337399920
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
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Question
Chapter 9, Problem 17RQ
To determine
The spectral class, luminosity class, type and color of star.
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Chapter 9 Solutions
Foundations of Astronomy (MindTap Course List)
Ch. 9 - Prob. 1RQCh. 9 - Why was the Hipparcos satellite able to make more...Ch. 9 - Prob. 3RQCh. 9 - Prob. 4RQCh. 9 - Prob. 5RQCh. 9 - Prob. 6RQCh. 9 - Prob. 7RQCh. 9 - Prob. 8RQCh. 9 - Prob. 9RQCh. 9 - Prob. 10RQ
Ch. 9 - Prob. 11RQCh. 9 - Prob. 12RQCh. 9 - Prob. 13RQCh. 9 - Prob. 14RQCh. 9 - Prob. 15RQCh. 9 - Prob. 16RQCh. 9 - Prob. 17RQCh. 9 - Prob. 18RQCh. 9 - Prob. 19RQCh. 9 - Prob. 20RQCh. 9 - Prob. 21RQCh. 9 - Prob. 22RQCh. 9 - Prob. 23RQCh. 9 - Prob. 24RQCh. 9 - Prob. 25RQCh. 9 - Prob. 26RQCh. 9 - Prob. 27RQCh. 9 - Prob. 28RQCh. 9 - Prob. 29RQCh. 9 - Prob. 30RQCh. 9 - Prob. 31RQCh. 9 - Prob. 32RQCh. 9 - How Do We Know? In what way are basic scientific...Ch. 9 - Prob. 1PCh. 9 - Prob. 2PCh. 9 - Prob. 3PCh. 9 - Prob. 4PCh. 9 - Complete the following table:Ch. 9 - Prob. 6PCh. 9 - Prob. 7PCh. 9 - Prob. 8PCh. 9 - Prob. 9PCh. 9 - Prob. 10PCh. 9 - Prob. 11PCh. 9 - Prob. 12PCh. 9 - Prob. 13PCh. 9 - Prob. 14PCh. 9 - Prob. 15PCh. 9 - Prob. 16PCh. 9 - Prob. 17PCh. 9 - Prob. 18PCh. 9 - Prob. 19PCh. 9 - Prob. 20PCh. 9 - Prob. 1SOPCh. 9 - Prob. 2SOPCh. 9 - Prob. 3SOPCh. 9 - Look at the image on the opening page of this...Ch. 9 - Prob. 2LTLCh. 9 - Prob. 3LTLCh. 9 - Prob. 4LTL
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- 12. A star with spectral type MO has a surface temperature of 3750 K and a radius of 0.63 Rsun: How many times more luminous is this star than the Sun? (if it is less luminous enter a number less than one) Answer: Submit All Answers Last Answer: 0.0923 Incorrect, tries 1/5. Hint: Use the Luminosity equation, which says that L is proportional to R^2 T^4. If you keep these as ratios compared to the sun, your L will also come out as a ratio compared to the Sun. This star has a mass of 0.4 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. Answer: Submit All Answers Compare this to the lifetime of a MO 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.) Answer: Submit All Answersarrow_forwardChoose the statements that correctly describe the characteristics of the stars located in the labeled quadrants of the H-R diagram. Luminosityarrow_forwardSuppose a star has a luminosity of 7.0x1026 watts and an apparent brightness of 4.0x10-12 watt/m?. How far away is it? Give your answer in both kilometers and light-years.arrow_forwardEach choice below lists a spectral type and luminosity class for a star. Which one is a hot main sequence star? OA. spectral type 09, luminosity class I O B. spectral type 01, luminosity class V O C. spectral type M2, luminosity class I OD. spectral type M2, luminosity class Varrow_forwardIf the stars Betelgeuse and Rigel each have the same luminosity, but the temperature of Betelgeuse is lower than Rigel, which star has the greater surface area? O A. Betelgeuse B. Rigel O C. They are the same size. OD. There is insufficient information to answer this question.arrow_forward12: A 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) Answer: 36.854 13:This star has a mass of 3.3 MSun. what is the main sequence lifetime of this star? You may assume that the lifetime of the sun is 1010 yr. Please answer question 13 thank you.arrow_forwardStar 1 and star 2 have the same V-magnitude, V = 7.5. However, they have different B-magnitudes, B1 = 7.2 and B2 = 8.5. If star 2 has a distance that is 10 times further than star 1, what are the luminosity ratios, L1/L2, in both B- and V-bands?arrow_forwardWhich of the following binary star systems cannot exist? A. A 1 solar-mass main sequence star and a 4 solar mass red giant with a size 100 times smaller than the orbital distance. B. A 15 solar-mass main sequence star and a 10 solar mass red giant with a size 100 times smaller than the orbital distance. C. A 1 solar-mass main sequence star and a 4 solar-mass main sequence star. D. A 2 solar-mass main sequence star and a 1 solar mass red giant with a size a few times smaller than the orbital distance.arrow_forwardChoose the correct statements concerning spectral classes of stars. (Give ALL correct answers, i.e., B, AC, BCD...) A) Neutral hydrogen lines dominate the spectrum for stars with temperatures around 10,000 K because a lot of the hydrogen is in the n=2 level. B) Hydrogen lines are weak in type O-stars because most of it is completely ionized. C) Oh Be A Fine Guy/Girl Kiss Me, is a mnemonic for remembering spectral classes. D) The spectral sequence has recently been expanded to include L, T, and Y classes. E) K-stars are dominated by lines from ionized helium because they are so hot. F) The spectral types of stars arise primarily as a result of differences in temperature.arrow_forwardIf a star has a surface temperature of 3000 K but a luminosity 150 times greater than our Sun, what size is this star? Give your answer in units of the solar radius, R .arrow_forwardThe spectral type of a star is directly related to its color. Recall that a star emits light as a blackbody, which has a particular shape to its spectrum, as shown in this figure. Based on this, what basic property of a star determines its color (and thus its spectral type)? Choose one: A. age B. composition C. radius D. temperaturearrow_forwardTwo stars are identified on the Hertzsprung-Russell diagram below. Hertzsprung-Russell Diagram Temperature (K) 40,000 20,00010,000 7,500 5,500 4,500 3,000 10 10 10 www 10 10 B. G K M Spectral Class Based on this diagram, how do the characteristics of Star 1 and Star 2 compare? Star 1 is cooler and less bright than Star 2. O Star 1 is hotter and brighter than Star 2. O Star 1 is cooler and brighter than Star 2. O Star 1 is hotter and less bright than Star 2. O Aisoujunarrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_ios
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