How Has the Diameter of the Black Hole Candidate Cygnus

question 18

Multiple Choice

How has the diameter of the black hole candidate Cygnus X-1 been estimated?

• A) from the angular size in the sky of Cygnus X-1 and its known distance from Earth
• B) from the time scale of the flickering of the X-rays Cygnus X-1 emits
• C) from the orbital period around a companion star of Cygnus X-1
• D) from the length of time Cygnus X-1 blocks off the light from its companion star when Cygnus X-1 passes in front of (eclipses) its companion, as seen from Earth

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Definitions:

Mechanism

The detailed process or steps through which a chemical reaction occurs, explaining how reactants are transformed into products.

Reaction

A process in which substances, the reactants, transform into different substances, the products, through breaking and forming of chemical bonds.

Organic Chemistry

The scientific study of the structure, properties, composition, reactions, and synthesis of organic compounds that contain carbon in covalent bonding.

Reaction

refers to a process in which one or more substances (reactants) are converted to one or more different substances (products).