What Appears to Be the Central Energy-Generating System or "Engine

question 219

Multiple Choice

What appears to be the central energy-generating system or "engine" that is producing prodigious amounts of energy in the centers of galaxies,active galaxies,and quasars?

• A) a steady series of supernova explosions, the late evolutionary stages of massive stars
• B) a rapidly rotating core of matter, where friction between it and the surrounding matter causes tremendous heat and energy output
• C) a supermassive black hole, where matter is compressed falling into the hole and heated to extremely high temperatures
• D) There is no central "engine" in these sources. Their high gravity has focused radiation from many sources beyond them by gravitational lensing and they thus appear to be very bright.

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Definitions:

Backward Conditioning

A conditioning procedure where the conditioned stimulus is presented after the unconditioned stimulus, making it less effective for learning associations.

US Presented

Typically means how specific concepts, ideas, or findings are introduced or demonstrated in the United States.

CS

In the context of classical conditioning, CS stands for Conditioned Stimulus, which is a previously neutral stimulus that, after association with an unconditioned stimulus, comes to trigger a conditioned response.

Second-order Conditioning

This is a process in which a stimulus that's already linked to a response becomes associated with another, new stimulus, creating a second conditioned stimulus.