Why Did the Solar Nebula Heat Up as It Collapsed

question 69

Multiple Choice

Why did the solar nebula heat up as it collapsed?

• A)Radiation from other nearby stars that had formed earlier heated the nebula.
• B)The shock wave from a nearby supernova heated the gas.
• C)Collisions among planetesimals generated friction and heat.
• D)Nuclear fusion occurring in the core of the protosun produced energy that heated the nebula.
• E)As the cloud shrank, its gravitational potential energy was converted to thermal energy.

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Definitions:

Visual Recognition Memory

The capacity to recall and identify visuals that have been seen before.

Receptive Vocabulary

The number of words one understands.

Expressive Vocabulary

The number of words one can use in the production of language.

Babble

The sounds, syllables, and simple vocalizations produced by infants and young children as they begin to learn language.