What Is the Primary Practical Difficulty That Limits the Use

question 91

Multiple Choice

What is the primary practical difficulty that limits the use of Hubble's law for measuring distances?

• A)Redshifts of galaxies are difficult to measure.
• B)The recession velocities of distant galaxies are so great that they are hard to measure.
• C)We do not know Hubble's constant very accurately yet.
• D)Hubble's law is only useful theoretically;it is difficult to use in practice.
• E)The motion of Earth relative to the Milky Way is difficult to account for.

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Definitions:

Recency Effect

The psychological phenomenon where the most recently presented items or experiences are more likely to be remembered than those presented earlier.

State-dependent Memory

The occurrence where data acquired while in a specific emotional condition (for example, joy or sorrow) is more readily remembered when one is again in that emotional state.

Tranquilizing Drug

Medications used to reduce tension or anxiety, functioning typically by depressing the central nervous system.

Test Anxiety

The extreme stress, anxiety, and discomfort some individuals feel before or during examinations, negatively affecting performance.