A Galaxy Rotation Curve Is a Plot of the Rotation

question 68

Multiple Choice

A galaxy rotation curve is a plot of the rotation speed as a function of the:

• A) galaxy's luminosity
• B) mass of the dark matter halo
• C) brightness of the luminous matter in the galaxy
• D) radius from the center
• E) ages of star clusters

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Definitions:

Independent Variable

In an experiment, the variable that is manipulated or changed by the researcher to observe its effect on the dependent variable.

Research Hypothesis

A specific, testable prediction about the relationship between at least two variables in a population, based on theory or previous research.

Independent Variable

A variable that is manipulated by the researcher to observe its effect on the dependent variable.

Research Hypothesis

A specific, clear, and testable statement predicting a particular outcome or difference based on theoretical grounds or previous research.