Trumpler Discovered the Effect of Interstellar Dust by Comparing Two

question 129

Multiple Choice

Trumpler discovered the effect of interstellar dust by comparing two different distance measurements of distant clusters. The first was based on appearance (concentration of stars toward the center, etc.) , which was unaffected by dust. The other was spectroscopic parallax (use of the H-R diagram) , which was affected by dust. What should such a comparison show?

• A) The H-R diagram should always give larger distances.
• B) The H-R diagram should always give smaller distances.
• C) There should be no difference in the distances.
• D) The distances should be different, but sometimes the H-R diagram should give the larger distance and sometimes the smaller distance depending on the actual distance to the cluster.

---

Definitions:

Cognitive Appraisal

The process by which an individual evaluates and interprets a situation or stimulus to determine its significance for his or her well-being.

Zajonc

A psychologist known for his work in social and cognitive processes and specifically for his theories on social facilitation and the mere exposure effect.

Lazarus

Refers to Richard Lazarus, a psychologist known for his theory on stress and emotion focusing on cognitive appraisal.

Emotional Reactions

Responses driven by one's feelings to certain stimuli or situations, involving physiological, behavioral, and cognitive aspects.