Question

The velocity of light in vacuum is 3 x 10^8 m/s and in glass is 2 x 10^8 m/s. The refractive index of glass is?

​

Answer 1

$\huge\mathcal\colorbox{purple}{{\color{pink}\huge\ {Aɴsᴡᴇʀ \: }}}$

Answer :

• ›› The refractive index of glass is 1.5.

Explanation :

Given :

• Velocity of light in vacuum = 3 × 10⁸ m/s.
• Velocity of light in glass = 2 × 10⁸ m/s.

To Find :

• Refractive index of glass = ?

Formula required :

Formula to calculate the refractive index of glass is given by,

• → μ = c/v.

Here,

• μ is the refractive index of glass.
• c is the velocity of light in vacuum.
• v is the velocity of light in glass.

Solution :

As we are given with the velocity of light in vacuum and velocity of light in glass them we know the required formula, that is,

→ μ = c/v.

By using the formula to calculate refractive index of glass and substituting all the given values in the formula, we get :

→ μ = 3 × 10⁸/2 × 10⁸

→ μ = 3/2

→ μ = 1.5

• Hence, the refractive index of glass is 1.5.

Answer 2

$\huge \colorbox{yellow}{ || ąŋʂῳɛཞ || }$

Glass refractive index is defined as the ratio between the speed of light in the vacuum and the speed of light in the glass.

Refractive index of glass (ng) = Speed of light in vacuum/speed of light in the glass.

ng = (3 ×108)/ (2 ×108)

ng = 1.5