EBK FOUNDATIONS OF ASTRONOMY
14th Edition
ISBN: 8220106820612
Author: Backman
Publisher: YUZU
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Chapter 12, Problem 1SOP
To determine
The lifespan on the main-sequence of an
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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).
=
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/L
12: 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.
Chapter 12 Solutions
EBK FOUNDATIONS OF ASTRONOMY
Ch. 12 - Prob. 1RQCh. 12 - Prob. 2RQCh. 12 - Prob. 3RQCh. 12 - Prob. 4RQCh. 12 - Prob. 5RQCh. 12 - Describe the law of hydrostatic equilibrium.Ch. 12 - Prob. 7RQCh. 12 - Prob. 8RQCh. 12 - Prob. 9RQCh. 12 - Prob. 10RQ
Ch. 12 - Prob. 11RQCh. 12 - Prob. 12RQCh. 12 - Prob. 13RQCh. 12 - Prob. 14RQCh. 12 - Prob. 15RQCh. 12 - Prob. 16RQCh. 12 - Prob. 17RQCh. 12 - Prob. 18RQCh. 12 - Prob. 19RQCh. 12 - What gives the triple-alpha process its name? Why...Ch. 12 - Prob. 21RQCh. 12 - Prob. 22RQCh. 12 - Prob. 23RQCh. 12 - Prob. 24RQCh. 12 - Prob. 25RQCh. 12 - Prob. 26RQCh. 12 - Prob. 27RQCh. 12 - Prob. 28RQCh. 12 - Prob. 29RQCh. 12 - Prob. 30RQCh. 12 - Prob. 31RQCh. 12 - How Do We Know? How can mathematical models allow...Ch. 12 - Prob. 1PCh. 12 - Prob. 2PCh. 12 - Prob. 3PCh. 12 - Prob. 4PCh. 12 - Prob. 5PCh. 12 - Prob. 6PCh. 12 - Prob. 7PCh. 12 - Prob. 8PCh. 12 - Prob. 9PCh. 12 - Prob. 10PCh. 12 - Prob. 11PCh. 12 - Prob. 12PCh. 12 - Prob. 13PCh. 12 - Prob. 14PCh. 12 - Prob. 15PCh. 12 - Prob. 16PCh. 12 - Prob. 1SOPCh. 12 - Prob. 2SOPCh. 12 - Prob. 1LTLCh. 12 - Prob. 2LTLCh. 12 - Prob. 3LTLCh. 12 - Prob. 4LTLCh. 12 - Prob. 5LTL
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- 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_forwardLet's calculate how much mass will be lost by the Sun 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 that it is only the core of the star that is hot enough for fusion). During nuclear fusion, the Sun converts about 0.7% of the core hydrogen mass into energy. The total mass of the Sun is 2 × 1030 kg. How many kilograms of mass will be converted to energy during the main sequence stage of the Sun's life? What is the ratio of this lost mass to the Earth's mass (6 × 1024 kg)? In other words, how many Earths of mass will be turned into energy?arrow_forwardStar A and Star B are both on the main sequence. Star A is 74 times more luminous than Star B. What is the ratio of their main-sequence lifetimes? Hint: Refer to the stellar life expectancies equation,arrow_forward
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