Two Stars Have the Same Spectral Classification,say,M2,but One of Them

question 50

Multiple Choice

Two stars have the same spectral classification,say,M2,but one of them is a red giant while the other is a main-sequence star.To determine which is which,we look at their spectra because (see Figure 10-9,Comins,Discovering the Essential Universe,6th ed.) the absorption lines in the giant will be:

• A) narrower because of the pressure difference between the atmospheres of the two stars.
• B) broader because of the pressure difference between the atmospheres of the two stars.
• C) narrower because of the temperature difference between the two luminosity classes.
• D) broader because of the temperature difference between the two luminosity classes.

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Definitions:

Great Awakening

A series of religious revivals in the American colonies in the 18th and early 19th centuries that emphasized emotional spirituality over traditional doctrine.

Religious Emotionalism

Powerful and expressive displays of religious fervor and emotion, often associated with revivalist and charismatic movements.

American Colonies

The English settlements along the Atlantic coast of North America in the 17th and 18th centuries, which later formed the United States.

Republicanism

A political belief system focused on the concept of citizenship within a republic, where sovereignty is vested in the populace.