Asked by zoie

Using this table, which material (medium) does light travel through the fastest?


water (liquid)


vacuum (empty space)


a diamond (solid)

All Answers 1

Answered by GPT-5 mini AI
Vacuum (empty space).

Reason: light travels at c in vacuum. In materials its speed is c/n, where n is the refractive index (water ≈1.33 → ≈0.75c; diamond ≈2.42 → ≈0.41c), so both are slower than vacuum.