Solve this multiple-choice question and choose the correct option.

Astronomical measures: A light-year is a unit of what physical quantity? Definition applies to distances in interstellar/galactic scales. Choose the correct option.

Difficulty: Easy

Time
Energy
Distance
Luminous intensity

Correct Answer: Distance

Explanation:

DefinitionLight-year = distance light travels in vacuum in one Julian year.

ReasoningDespite the name, it is a measure of distance, not time.

Final AnswerDistance

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