Before a Giant Molecular Cloud Can Contract Gravitationally, It Must

question 9

Essay

Before a giant molecular cloud can contract gravitationally, it must overcome four physical factors that resist compression.  What are these four factors?

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Definitions:

Pyroclastic Eruption

A volcanic phenomenon involving the expulsion of hot gases, ash, and volcanic debris.

Dissolved Gas

Gases that are incorporated into magma and can expand, leading to explosive volcanic eruptions as pressure decreases.

Rhyolite

A mostly fine-grained, felsic igneous rock, generally of volcanic origin; can contain glass, volcanic ash, pieces of pumice, and variable amounts of visible crystals (phenocrysts).

Thermal Energy

The internal energy present in a system due to the random movements of its molecules or atoms.