Concept explainers
(a)
The lifetime of a star; compare it with given values in Table 12.1.
(a)
Answer to Problem 38QAP
The lifetime of star is
Explanation of Solution
Write the expression for lifetime of a main sequence star.
Here,
The above expression shows that the lifetime of star is inversely proportional to the mass of main-sequence star. Greater the mass of star compared to the Sun is; less would be its lifetime.
Conclusion:
Substitute
Thus, the lifetime of star is
(b)
The lifetime of a star; compare it with given values in Table 12.1.
(b)
Answer to Problem 38QAP
The lifetime of star is
Explanation of Solution
Write the expression for lifetime of a main sequence star.
Here,
The above expression shows that the lifetime of star is inversely proportional to the mass of main-sequence star. Greater the mass of star compared to the Sun is; less would be its lifetime.
Conclusion:
Substitute
Thus, the lifetime of star is
(c)
The lifetime of a star; compare it with given values in Table 12.1.
(c)
Answer to Problem 38QAP
The lifetime of star is
Explanation of Solution
Write the expression for lifetime of a main sequence star.
Here,
The above expression shows that the lifetime of star is inversely proportional to the mass of main-sequence star. Greater the mass of star compared to the Sun is; less would be its lifetime.
Conclusion:
Substitute
Thus, the lifetime of star is
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Chapter 12 Solutions
UNDERSTANDING OUR UNIVERSE W/WKBK+ACCES
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- What is the average density of a neutron star that has the same mass as the sun but a radius of only 49.665 km? (Pls state the answer in the proper SI unit and without scientific notation)arrow_forwardwhat is the answer for sub-item (b) if the radius of the neutron star is 78.795 km? (please express your answer in the proper SI unit and without scientific notation)arrow_forwardIf the radius of the neutron star is 85.074 km, what is the average density of a neutron star that has the same mass as the sun but a radius of only 20.0 km? (express your answer in the proper SI unit and without scientific notation)arrow_forward
- What is the ratio of the percent of metals in extreme Population I stars (3%) to that in extreme Population II stars (0.05%)? NpopI NpopII =arrow_forwardWhat are the a) luminosity and b)wavelength of maximum emission for a star with a surface temperature is 2,000K and a size of 1.0*108m?arrow_forwardIn Exercise 12.4 of your book, University Physics 15th edition (see End of the Chapter 12 section), what is the answer for sub-item (b) if the radius of the neutron star is 6.676 km? (express your answer in the proper SI unit and without scientific notation) Exercise 12.4 : What is the average density of a neutron star that has the same mass as the sun but a radius of only 20.0 km?arrow_forward
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