UNIVERSE (LOOSELEAF):STARS+GALAXIES
6th Edition
ISBN: 9781319115043
Author: Freedman
Publisher: MAC HIGHER
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Question
Chapter 16, Problem 49Q
To determine
(a)
The distance of arches extends above the Sun’s surface.
To determine
(b)
The reason of the photosphere appears dark compared to arches.
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Given that the solar spectrum corresponds to a temperature of T- 5800K and peaks at a
wavelength of à = 500 nm, use Wien's law to determine the wavelength (2') corresponding to
the peak of the blackbody curve (a) in the core of the Sun, where the temperature is T' - 10'K, (b)
in the solar convection zone (10° K), and (c) just below the solar photosphere (10* K). [Hint:
AT - A'T' (why?)] What form (visible, infrared, X ray, etc.) does the radiation take in each case?
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.
An image of the disk of the Sun shows a higher brightness at the centre compared to the edges. Explain with the aid of a sketch the reasons for this darkening at the limb of the solar disk.
In images of the solar photosphere there are small regions of the solar disk, about 500 km across, which are about 2.5 times brighter that the surrounding photosphere. Assuming a temperature of 5800 K for the background photosphere, calculate the temperature of these photospheric bright points.
One explanation for these bright points is that the density is lower in these regions. Explain briefly how that could produce the observed brightening.
Chapter 16 Solutions
UNIVERSE (LOOSELEAF):STARS+GALAXIES
Ch. 16 - Prob. 1QCh. 16 - Prob. 2QCh. 16 - Prob. 3QCh. 16 - Prob. 4QCh. 16 - Prob. 5QCh. 16 - Prob. 6QCh. 16 - Prob. 7QCh. 16 - Prob. 8QCh. 16 - Prob. 9QCh. 16 - Prob. 10Q
Ch. 16 - Prob. 11QCh. 16 - Prob. 12QCh. 16 - Prob. 13QCh. 16 - Prob. 14QCh. 16 - Prob. 15QCh. 16 - Prob. 16QCh. 16 - Prob. 17QCh. 16 - Prob. 18QCh. 16 - Prob. 19QCh. 16 - Prob. 20QCh. 16 - Prob. 21QCh. 16 - Prob. 22QCh. 16 - Prob. 23QCh. 16 - Prob. 24QCh. 16 - Prob. 25QCh. 16 - Prob. 26QCh. 16 - Prob. 27QCh. 16 - Prob. 28QCh. 16 - Prob. 29QCh. 16 - Prob. 30QCh. 16 - Prob. 31QCh. 16 - Prob. 32QCh. 16 - Prob. 33QCh. 16 - Prob. 34QCh. 16 - Prob. 35QCh. 16 - Prob. 36QCh. 16 - Prob. 37QCh. 16 - Prob. 38QCh. 16 - Prob. 39QCh. 16 - Prob. 40QCh. 16 - Prob. 41QCh. 16 - Prob. 42QCh. 16 - Prob. 43QCh. 16 - Prob. 44QCh. 16 - Prob. 45QCh. 16 - Prob. 46QCh. 16 - Prob. 47QCh. 16 - Prob. 48QCh. 16 - Prob. 49QCh. 16 - Prob. 50QCh. 16 - Prob. 51QCh. 16 - Prob. 52QCh. 16 - Prob. 53QCh. 16 - Prob. 54QCh. 16 - Prob. 55QCh. 16 - Prob. 56QCh. 16 - Prob. 57QCh. 16 - Prob. 58QCh. 16 - Prob. 59QCh. 16 - Prob. 60Q
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