Question

Will light travel through a glass slab with the same velocity as it travels in air?

Answer 1

No. Light does not travel through a glass slab with the same velocity as it travels in air.

• Light travels faster in air and slower in glass because glass is an optically denser medium.
• The speed of light in a medium is given by:
  `n = c/v`

where:

• n = refractive index of the medium,
• c = speed of light in air (or vacuum),
• v = speed of light in the medium.

Since the refractive index of glass is greater than that of air, the speed of light in glass is lower.

Therefore, light travels more slowly through a glass slab than through air.