Final answer:
One light-year is approximately 9.46 trillion kilometers, making the statement that a light-year is about 10 trillion kilometers false. Light years are used as a measure for vast astronomical distances, such as the distance to the Andromeda Galaxy.
Step-by-step explanation:
A light-year is approximately 9.46 trillion kilometers, not 10 trillion kilometers. A light-year is the distance that light, which travels at 300,000 kilometers per second, covers in a single year.
With light traveling such vast distances, the light-year becomes an essential measure for astronomical distances. For example, the Andromeda Galaxy, the closest large galaxy to us, is about 2.00×106 light years away. This translates to an astronomical distance of approximately 1.892×1022 meters since one light-year equals 9.461×1012 meters.