One light year is equivalent to roughly how many kilometers?

Answer & Explanation

Correct answer: (D) 9.5 trillion kilometer

A light year is the distance that light travels in one year in a vacuum. It is a unit of astronomical distance used to measure vast distances in space.

Calculation

• Speed of light = approximately 300,000 km/s (299,792 km/s to be precise)
• Number of seconds in a year = 365.25 days × 24 hours × 60 minutes × 60 seconds
• Number of seconds in a year = 31,557,600 seconds

Distance = Speed × Time

• 1 light year = 300,000 km/s × 31,557,600 seconds
• 1 light year ≈ 9,460,730,472,580 km
• 1 light year ≈ 9.46 trillion kilometers (approximately 9.5 trillion kilometers)