Question

The speed of light in water is 2.25 x 108 m/s. If the speed of light in vacuum be 3 x 108 m/s, calculate the refractive index of water.

Answer 1

Answer:

Refractive index of water is 1.33

Explanation:

As it is known:

    n=c/v

c:speed of light in vaccum

v:speed of light in medium ,medium given is water,

Substituting the values:

  n=3×10^8/2.25×10^8

  n=1.33

refractive index is a unitless quantity because it is a ratio between two same quantities.

Hope it will help you!

Answer 2

Answer:

The speed of light in water is $2.25*10^{8} m/s$, the speed of light in a vacuum be $3*10^{8}m/s$, then the refractive index of water is $1.33$

Explanation:

When light travels from one medium to another medium with different refractive index its direction changes because light velocity depends on the medium through which it travels

The refractive index is the degree of the change in direction of the light

it can be expressed as $n=C/v$

where the velocity of light in a vacuum given as  $C=3*10^{8}m/s$

and  the velocity of light in a given medium is $v$

From the question, it is given that

the speed of light in water is $v=2.25*10^{8}m/s$

now the refractive index of water is $n=3*10^{8}/2.25*10^{8} =1.33$