An Astronomer Plots the H-R Diagram of a Star Cluster

question 225

Multiple Choice

An astronomer plots the H-R diagram of a star cluster and finds that it contains hot B-type stars on the main sequence and cooler G- and K-type stars noticeably above the main sequence. This cluster is

• A) very young because the G and K stars are still evolving toward the main sequence.
• B) of indeterminate age since the age of the cluster cannot be estimated from the information given.
• C) impossible because cool stars cannot exist above the main sequence when hot stars are on the main sequence.
• D) old because the G and K stars are already evolving off (away from) the main sequence.

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Definitions:

Psychological Discomfort

Psychological discomfort is a state of mental unease or distress, often resulting from challenging or conflicting beliefs, thoughts, or emotions.

Attitudes And Behaviors

Refers to the relationship between how individuals think and feel about various topics, objects, or individuals and how this affects their actions or reactions in various situations.

Effort Justification

The phenomenon where people attribute greater value to outcomes they had to put effort into achieving.

Cognitive Dissonance

The mental discomfort experienced by an individual who holds two or more contradictory beliefs, ideas, or values at the same time.