Multiple choice

Light year is a unit of

  1. intensity of light

  2. distance

  3. time

  4. planetary motion

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A light year is a unit of DISTANCE, not time. It represents the distance light travels in one vacuum year (approximately 9.46 trillion kilometers). Astronomers use it to measure vast interstellar and intergalactic distances.