Suppose We Observe a Source of X-Rays That Varies Substantially

question 107

Multiple Choice

Suppose we observe a source of X-rays that varies substantially in brightness over a period of a few days. What can we conclude?

• A) The X-ray source is no more than a few light-days in diameter.
• B) The X-ray source is a quasar.
• C) The X-ray source contains a black hole with an accretion disk.
• D) The X-ray source must have a strong, rapidly varying magnetic field.

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Definitions:

Robbery

The crime of taking or attempting to take anything of value by force, threat of force, or by putting the victim in fear.

Ground

The basis or reason for an action, belief, or assertion.

Larceny

The unlawful taking of personal property from another person with the intent to permanently deprive them of it.

Knowledge

Understanding, awareness, or familiarity gained through experience or education.