The Major Advantage of the Measurement of the 21-Cm Radio

question 104

Multiple Choice

The major advantage of the measurement of the 21-cm radio emission from hydrogen gas for investigating the spiral structure of our Galaxy is that

• A) Doppler shift of this narrow-wavelength line emission is caused by the temperature of the hot hydrogen gas and therefore can be used to measure the distribution and temperature of this important component of the Milky Way.
• B) it is relatively easily absorbed by hydrogen gas in the Milky Way so that measurements are not confused by emission of this radiation from other galaxies beyond the Milky Way.It originates only from cold hydrogen gas and can be used to map this important component.
• C) this emission can easily penetrate the Milky Way gas and dust and comes only from hot gas;hence,it can be used to map the distribution of hot hydrogen gas.
• D) radio waves easily penetrate the Milky Way dust and gas;it is a very narrow wavelength,thus its Doppler shift can be used to measure gas motions.

Recognize methods for social workers to enhance self-awareness about their interaction patterns with clients.

Understand key terminology and abbreviations related to the digestive system.

Recognize the processes involved in digestion and nutrient absorption.

Identify diagnostic terms, diseases, and disorders of the digestive system.

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Definitions:

Reappraisal

The cognitive process of changing one's emotional response by altering the meaning of the emotion-eliciting situation.

Altruistic Goals

Objectives aimed at benefiting others without expecting personal gain, reflecting selflessness and concern for the well-being of others.

Material Interests

Concerns or priorities based on tangible resources, assets, and physical or economic well-being rather than abstract or spiritual factors.

Physical Maturation

The biological growth processes that enable orderly changes in behavior, mostly independent of the environment but influenced by it.