What is a light-year, and how is it defined?
The significance of light year and its definition.
Answer to Problem 1CQ
A light-year is a unit of length used to measure the astronomical distances. It is defined as the distance travelled by the light in
Explanation of Solution
In astronomy, there were no referent points of comparison so that standard units were created for the measurement of distances. A light-year is a unit of length which is used to describe the astronomical distances.
Therefore, a light year is the distance travelled by the light in
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