The Star Sirius (α Canis Majoris)is Actually a Binary Star

question 227

Multiple Choice

The star Sirius (α Canis Majoris) is actually a binary star in which the brighter,more massive star (Sirius A) is an A-type main-sequence star and the fainter,less massive star (Sirius B) is a white dwarf.How is this system MOST likely to have formed?

• A) Sirius A formed as a single star and later captured a passing white dwarf.
• B) Sirius B formed first and evolved to become a white dwarf; capture of gas and dust from interstellar clouds then resulted in the formation of Sirius A.
• C) Sirius B was initially more massive than Sirius A and evolved faster; it then became less massive due to mass loss to space and mass transfer to Sirius A.
• D) Sirius A was always the more massive of the two and became a red giant; then mass transfer to Sirius B accelerated the evolution of Sirius B and caused it to become a white dwarf.

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Definitions:

Negative Linear Relationship

A direct relationship between two variables where an increase in one variable leads to a decrease in another.

Positive Linear Relationship

A relationship between two variables where an increase in one variable is associated with an increase in the other variable, depicted as a straight line.

No Relationship

A situation where two variables do not display any association, correlation, or cause-and-effect interaction with each other.

Independent Variable

The variable in an experiment that is manipulated by the researcher to examine its effect on the dependent variable.