Universe: Stars And Galaxies
6th Edition
ISBN: 9781319115098
Author: Roger Freedman, Robert Geller, William J. Kaufmann
Publisher: W. H. Freeman
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Chapter 17, Problem 48Q
To determine
The star which has greater luminosity and the amount by which it is greater.
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Chapter 17 Solutions
Universe: Stars And Galaxies
Ch. 17 - Prob. 1QCh. 17 - Prob. 2QCh. 17 - Prob. 3QCh. 17 - Prob. 4QCh. 17 - Prob. 5QCh. 17 - Prob. 6QCh. 17 - Prob. 7QCh. 17 - Prob. 8QCh. 17 - Prob. 9QCh. 17 - Prob. 10Q
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- 15: A star has a parallax angle of 0.0270 arcseconds and an apparent magnitude of 4.641. What is the distance to this star? Answer: 37 16: What is the absolute magnitude of this star? Answer:1.8 17: Is this star more or less luminous than the Sun? Answer "M" for More luminous or "L" for Less luminous. (HINT: the absolute magnitude of the Sun is 4.8) Answer: M 18: What is the luminosity of this star? (HINT: The luminosity of the Sun is 3.85×1026 W.) Please answer question #18, #15-17 are correct, the photos provide the work for them.arrow_forwardA star has a parallax angle of 0.0270 arcseconds and an apparent magnitude of 4.641. The distance to this star is 37.03 parsecs and the absolute magintude is 1.79. 18: What is the luminosity of this star? (HINT: The luminosity of the Sun is 3.85×1026 W.) Using the Forumla M1 - M2 = -2.5 log(L1/L2) the absolute magnitude of the Sun is 4.8arrow_forwardA star has a measured radial velocity of 300 km/s. If you measure the wavelength of a particular spectral line of Hydrogen as 657.18 nm, what was the laboratory wavelength (in nm) of the line? (Round your answer to at least one decimal place.) nm Which spectral line does this likely correspond to? Balmer-alpha (656.3 nm) Balmer-beta (486.1 nm) Balmer-gamma (434.0 nm) Balmer-del ta (410.2 nm)arrow_forward
- = A star population is composed of stars with masses in the range between 1M and 150M. The initial mass function is = 0 (M/M)-2.3, where o (Mo). The luminosity of a star = (M/M) 3.3. Calculate the percentage of the total luminosity of the stars in the population which is produced by stars with mass between 120M and 150M. scales with its mass as L/Larrow_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_forwardWhich star in the table below has the least surface temperature? Star Name d (parsecs) Parallax (seconds of arc) Spectral Type $$ \delta $$ Cen 0.026 B2 IV HR 4607 0.039 G8 III HR 4758 20 G0 V HR 39801 0.005 M2 I 9 CMa 2.5 A1 V a. $$ \delta $$ Cen b. HR 4607 c. HR 4758 d. HD 39801 e. 9 CMaarrow_forward
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