Which of the Following Is Necessary to Measure the Distance

question 53

Multiple Choice

Which of the following is necessary to measure the distance to a galaxy with Hubble's law?

• A) the Doppler effect formula
• B) resolving a Cepheid variable in the galaxy
• C) the size of the solar system
• D) the rotation velocity of the galaxy

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Definitions:

Test Statistic

A numerical value calculated from a statistical test's data, used to determine whether to reject the null hypothesis.

Degrees Of Freedom

The number of independent values or quantities that can vary in the analysis without violating any constraints.

Significance Level

The probability threshold below which the null hypothesis is rejected in a statistical test, often denoted by alpha (α).

Cohen's D

A measure of effect size indicating the standardized difference between two means.