The Event That Settled the Shapley-Curtis Debate About "Spiral Nebulae

question 64

Multiple Choice

The event that settled the Shapley-Curtis debate about "spiral nebulae" was

• A) Edwin Hubble measuring the distance to the Andromeda Galaxy.
• B) Arno Penzias and Robert Wilson detecting the cosmic microwave background radiation.
• C) Albert Einstein showing that gravity can bend the path of light.
• D) Edwin Hubble showing that the universe was expanding.

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Definitions:

Extrinsic Motivation

Motivation that is driven by external rewards such as money, fame, grades, and praise.

Subject Interesting

A subjective assessment indicating how much an individual is intrigued, engaged, or finds a specific topic or activity appealing.

Drive Motivation

An internal state that energizes, orients, and selects behavior to fulfill a need or achieve a goal.

Extrinsic Motivation

Motivation driven by external rewards such as money, fame, grades, or praise, rather than by intrinsic satisfaction in the activity itself.