How Do We Know That the Compact Object in Some

question 65

Multiple Choice

How do we know that the compact object in some X-ray binaries must be a black hole?

• A) X-rays of high enough energy can be emitted only by a black hole.
• B) The orbital period of the binary requires the compact object to have more than 1.4 solar masses.
• C) The orbital period of the binary requires the compact object to have more than 3 solar masses.
• D) The compact object does not produce any X-rays.

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Definitions:

Conjunctions

Words that join together sentences, clauses, phrases, or words, such as "and," "but," and "or."

Conjunctive Adverbs

Words that connect two independent clauses or sentences, showing relationship in terms of sequence, contrast, cause and effect, or other relationships.

Punctuated Correctly

Texts or sentences that have been properly marked with punctuation symbols to clarify meaning and indicate pauses or stops.

Conjunctive Adverbs

Words that connect two independent clauses together while also providing a transition that shows a relationship between them, like "however", "therefore", or "meanwhile".