Question

light enters from air to glass having refrective index 1.5 . what is the speed of light in glass? the speed of light in vaccum is 10​
please answer this it's urgent!!

Answer 1

Answer:-

Speed of light in glass is 2 × 10⁸ m/s .

Explanation:-

We have :-

→ Refractive index of glass = 1.5

→ Speed of light in vaccum = 3 × 10⁸ m/s

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Now, we know that :-

n = c/v

Where :-

• n is the refractive index of a given medium.

• c is the speed of light in vaccum.

• v is the speed of light in given medium.

Substituting values, we get :-

⇒ 1.5 = 3 × 10⁸/v

⇒ 1.5v = 3 × 10⁸

⇒ v = 3 × 10⁸/1.5

⇒ v = 2 × 10⁸ m/s

Some Extra Information:-

Refractive indices of some other mediums are :-

• Water = 1.33

• Kerosene = 1.41

• Diamond = 2.42

• Benzene = 1.50

Answer 2

Given :-

Refractive index = 1.5

Speed of light in space = 3 × 10⁸ m/s

To Find :-

Speed of light in  glass

Solution :-

According to the question we have to find speed of light in glass. Before solving we have to know it's formula

ng = c/v

ng = Refractive index

c = speed of light in Vaccum

v = Speed of light in glass

Given,

ng = 1.5

c =3 × 10⁸

By putting values

1.5 = 3 × 10⁸ / v

v = 3 × 10⁸/1.5

v = 2 × 10⁸ m/s

Therefore

• Speed of light in glass is 2 × 10⁸ m/s