Foundations of Astronomy (MindTap Course List)
14th Edition
ISBN: 9781337399920
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
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Chapter 8, Problem 8P
To determine
The line observed at the wavelength. Is it a blueshift or redshift. Does this gas is rising, sinking or moving.
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If the hottest star in the Carina Nebula has a surface temperature of 51,000 K, at what wavelength (in nm) does it radiate the most energy?
Hint: Use Wien's law:
?max =
2.90 ✕ 106 nm · K
T
How does that compare with 91.2 nm, the wavelength of photons with just enough energy to ionize hydrogen?
-The wavelength calculated above is shorter than 91.2 nm. Photons at this calculated wavelength will have more than enough energy to ionize hydrogen.
-The wavelength calculated above is longer than 91.2 nm. Photons at this calculated wavelength will have more than enough energy to ionize hydrogen.
-The wavelength calculated above is shorter than 91.2 nm. Photons at this calculated wavelength will not have enough energy to ionize hydrogen.
-The wavelength calculated above is longer than 91.2 nm. Photons at this calculated wavelength will not have enough energy to ionize hydrogen.
A cloud of mean number density n ~ 3000 cm-3 and radius 3 pc has an ionising
source with luminosity at 13.6 eV of L13.6eV = 2.18 x 109 erg s- at the centre.
(a) What is the size of the HII region in pe? [og = 2 x 10-13 cms-].
%3D
(b) What assumptions are involved in part
a)
(c) Discuss why the HII region will drive a shock into the rest of the cloud, and
calculate the post-shock density.
(d) Show why this HII region will destroy the cloud.
For 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.)
Chapter 8 Solutions
Foundations of Astronomy (MindTap Course List)
Ch. 8 - Prob. 1RQCh. 8 - Prob. 2RQCh. 8 - Prob. 3RQCh. 8 - Prob. 4RQCh. 8 - Prob. 5RQCh. 8 - Prob. 6RQCh. 8 - What evidence can you give that granulation is...Ch. 8 - Prob. 8RQCh. 8 - Prob. 9RQCh. 8 - Prob. 10RQ
Ch. 8 - Prob. 11RQCh. 8 - Prob. 12RQCh. 8 - Prob. 13RQCh. 8 - Prob. 14RQCh. 8 - Energy can be transported by convection,...Ch. 8 - Prob. 16RQCh. 8 - Prob. 17RQCh. 8 - Prob. 18RQCh. 8 - Prob. 19RQCh. 8 - Meridional is derived from meridian. Look up the...Ch. 8 - Prob. 21RQCh. 8 - Prob. 22RQCh. 8 - How can solar flares affect Earth?Ch. 8 - Prob. 24RQCh. 8 - Why does nuclear fusion require high temperatures...Ch. 8 - Prob. 26RQCh. 8 - Four protons are combined in the proton-proton...Ch. 8 - Give an example of a charged subatomic particle...Ch. 8 - Prob. 29RQCh. 8 - Prob. 30RQCh. 8 - Prob. 31RQCh. 8 - Prob. 32RQCh. 8 - Prob. 33RQCh. 8 - The radius of the Sun is 0.7 million km. What...Ch. 8 - Prob. 2PCh. 8 - Prob. 3PCh. 8 - What is the angular diameter of a star the same...Ch. 8 - If a sunspot has a temperature of 4200 K and the...Ch. 8 - How many watts of radiation does a 1-meter-square...Ch. 8 - If a sunspot has a temperature of 4200 K and the...Ch. 8 - Prob. 8PCh. 8 - Prob. 9PCh. 8 - Prob. 10PCh. 8 - Prob. 11PCh. 8 - Prob. 12PCh. 8 - Prob. 13PCh. 8 - Prob. 14PCh. 8 - The United States consumes about 2.5 1019 J of...Ch. 8 - Prob. 16PCh. 8 - Prob. 1SOPCh. 8 - Prob. 2SOPCh. 8 - Whenever there is a total solar eclipse, you can...Ch. 8 - Prob. 2LTLCh. 8 - Prob. 3LTLCh. 8 - Prob. 4LTLCh. 8 - The two images here show two solar phenomena. What...Ch. 8 - Prob. 6LTL
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