The Definition of a Main-Sequence Star Is a Star

question 228

Multiple Choice

The definition of a main-sequence star is a star

• A) with a surface temperature equal to that of the Sun.
• B) in which nuclear fusion reactions generate sufficient energy to oppose further compression of the star.
• C) whose age after birth is about 1 million years.
• D) with a luminosity precisely equal to that of the Sun.

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Definitions:

Unconditioned Stimulus

A stimulus that naturally triggers a reflexive response without any prior learning in classical conditioning.

Little Albert

Little Albert was the subject of an experiment by John B. Watson, demonstrating that classical conditioning could induce a fear response in humans.

Psychologists

Professionals in the field of psychology who study mental processes and behavior in humans and animals, often providing mental health care and counseling.

Unconditioned Response

A natural, automatic reaction to a stimulus that occurs without prior conditioning or learning.