What Do We Mean When We Say That the Rotation

question 30

Multiple Choice

What do we mean when we say that the rotation curve for a spiral galaxy is "flat"?

• A)The amount of light emitted by stars at different distances is about the same throughout the galaxy.
• B)Gas clouds orbiting far from the galactic center have approximately the same orbital speed as gas clouds located further inward.
• C)The disk of a spiral galaxy is quite flat rather than spherical like the halo.
• D)All the galaxy's mass is concentrated in its flat,gaseous disk.

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Definitions:

Decentration

The ability to consider multiple aspects of a situation simultaneously, characteristic of cognitive development in children.

Stimulant

A substance that increases physiological or nervous activity in the body, enhancing alertness, attention, and energy.

Attention-Deficit/Hyperactivity Disorder

Attention-Deficit/Hyperactivity Disorder, or ADHD, is a neurodevelopmental disorder characterized by patterns of hyperactivity, impulsivity, and/or inattention that are more frequent and severe than typically observed in individuals at a comparable level of development.

Melanin

The pigment responsible for determining skin, hair, and eye color in humans and animals, also providing some protection against the effects of UV radiation.