What Is the Physical Reason That Astronomers Can Find the Luminosity

question 91

Multiple Choice

What is the physical reason that astronomers can find the luminosity class (I,II,III,IV,or V) of a star using the star's spectrum?

• A) The relative amounts of hydrogen,helium,and other elements are different for stars of different luminosity classes.
• B) The absorption lines in the spectrum are affected by the density and pressure of the star's atmosphere.
• C) The absorption lines in the spectrum are affected by the star's surface temperature.
• D) The wavelength of maximum emission (given by Wien's law)is affected by the size of the star.

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Definitions:

Isomeric

Describes molecules having the same molecular formula but arranged in different structural configurations, leading to different physical and chemical properties.

1,2-dichloroethene

An organic compound with the formula C2H2Cl2, existing as two geometric isomers: cis and trans, used as a solvent and in the manufacture of other chemicals.

Isomeric Form

Refers to molecules that have the same molecular formula but differ in the arrangement of atoms or orientation in space, leading to different physical and chemical properties.

Dipole Moment

A measure of the separation of positive and negative charges in a system, indicating the polarity of a chemical bond or molecule.