Question

velocity of a light in medium is 1.5m/s its refractive index will be.
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Answer 1

Given

The velocity of light in a medium is 1.5 x 10⁸ m/s

To Find

Refractive index

Solution

We know that

$\sf \longrightarrow n=\dfrac{c}{v}$

Here

• n = Refractive index
• c = velocity of light in vacuum
• v = velocity of light in medium

According to the question

We are asked to find the refractive index

Therefore

We must find "n"

Given that

The velocity of light in a medium is 1.5 x 10⁸ m/s

Hence

• v = 1.5 x 10⁸ m/s

We know that

• c = 3 x 10⁸ m/s

Substituting the values

We get

$\sf \longrightarrow n=\dfrac{3 \times 10^{8}}{1.5 \times 10^{8}}$

Therefore

$\sf \longrightarrow n=2$

Hence

Refractive index = 2

Answer 2

Answer:

Given :

• Speed of light in a medium - 1.5 × 10^8 m/s

Find :

• Absolute refractive index of the medium.

Solution :

To find absolute refractive index of the medium ratio of speed of light in vacuum to speed of light in medium is calculated. It is given by the formula : -

n = c/v

• In the formula, n is refractive index, c is speed of light in vacuum and V is speed of light in medium.

Keeping the values in equation :

n = 3 × 10^8 / 1.5 × 10^8

n = 2

Thus, absolute refractive index of medium is 2.