Question

the speed of the light in air is 3*10^8m/s.and the speed of the light in water is 2.26*10^8m/s.find refractive index of water

Answer 1

Hola there,

Speed of light in air = 3 × 10^8

Speed of light in water = 2.26 × 10^8

Refractive index of water = Speed of light in air/speed of light in water

= (3 × 10^8)/(2.26 × 10^8)

= 1.32743363 ....Ans

Hope this helps...:)

Answer 2

Given:

The speed of light in air = 3 × $10^{8}$ m/s

The speed of light in water = 2.26 × $10^{8}$ m/s

To Find:

The refractive index of water

Solution

What is the refractive index of a medium?

• The refractive index of a medium is a measure of the extent of bending of light in that medium.
• It is the ratio of the speed of light in air and the speed of light in that medium.
• Mathematically,

                                          μ = $\frac{c}{v}$                                     (1)

• Since it is a ratio, it is dimensionless.

To find the solution to the given question, we will substitute known values in (1).

• It is given that c = 3 × $10^{8}$ m/s

                         and v = 2.26 × $10^{8}$ m/s

                                     ∴ μ = $\frac{3.10^{8} }{2.26 . 10^{8} }$

                                     ⇒μ = 1.33

Therefore, the refractive index of water is 1.33.