How Do Astronomers Know That Pulsating Variable Stars Are Actually

question 24

Multiple Choice

How do astronomers know that pulsating variable stars are actually expanding and contracting in diameter?

• A) it is clear just by looking at the light curve
• B) they discover this by looking at an H-R diagram
• C) they can measure a regularly varying Doppler shift in the spectral lines
• D) they can measure the star's changing pull on a companion star around it
• E) astronomers are just guessing; at the distances of the stars, there is no way to show that stars are expanding and contracting

---

Definitions:

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.

Psychological Discomfort

Describes a state of emotional unease or distress often triggered by stressful situations, conflicts, or challenging thoughts and beliefs.