Question

Whaita is the velocity of light in a diamond if the refractive index of diamond with respect to vacuum is $2.5$?

• A. $5\times {10}^8$
• B. $1.2\times {10}^{10}$
• C. $2.5\times {10}^8$
• D. $1.2\times {10}^8$

Answer 1

The correct option is D $1.2\times {10}^8$

Refractive index of a diamond $=$ Velocity of lihgt in vacuum/Velocity of light in the diamond
$2.5=3\times 10/\text{Velocity of light in the diamon}$
Velocity of light in the diamond $=3\times 10/2.5=1.2\times {10}^{8}m/s$