Question

If the speed of light in water is 3/4th of the speed of light in air than find the refractive index of water​

Answer 1

Given :

• Speed of light in water is 3/4 th of the speed of light in Air

To find :

• Refractive index of Water

Formula to be used :

The refractive index of a medium with respect to Air is given by the ratio of speed of light in air and speed of light in medium.

• n₁ = c / v

[ where n₁ is absolute R.I. of medium 1 , c is speed of light and v is speed of light in medium 1 ]

Solution :

Let, Refractive index of Water be n

Let, speed of light in Air be x

then, speed of light in water will be 3x/4

so,

→ n = (x) / (3x/4)

→ n = (x) (4/3x)

→ n = 4/3

therefore,

Refractive index of Water is 4/3 .