Science & Nature · 1
How fast does light travel in vacuum?
Answer
300,000 km/s
Light travels at approximately 299,792 kilometers per second (about 300,000 km/s) through the vacuum of space, a fundamental constant denoted by the letter 'c' in physics. This speed is the cosmic speed limit—nothing with mass can travel faster. The precise value of the speed of light was established through countless experiments and is now defined as an exact value in the International System of Units.
💡 Did you know?
When you look at the Sun, you're seeing it as it was 8 minutes and 20 seconds ago.
Other options people guess
- 150,000 km/s
- 450,000 km/s
- 600,000 km/s
Topics
- physics
- space
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