The Presence of Forbidden Lines in the Spectra of Emission

question 3

Multiple Choice

The presence of forbidden lines in the spectra of emission nebula indicates that the

• A) nebula has a very high temperature.
• B) nebula contains large amounts of hydrogen.
• C) gas in the nebula has a very low density.
• D) dust in the nebula is composed of very small grains of silicates and carbon.
• E) nebula is very near a star whose temperature is less than that of the sun.

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