How fast does light travel, in km per second?

Q: How fast does light travel, in km per second?

300,000 km/s (300,000). 300,000 km every second — seven and a half trips around Earth before you finish this sentence. Source: SI definition

300,000

km/s

300,000 km every second — seven and a half trips around Earth before you finish this sentence.SOURCESI definition

Scale check: 300,000 is roughly Wembley, full, plus a bit.

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