Question

Light enters from air into a glass plate having refractive index `1.50`. What is the speed of light in glass? The speed of light in vaccum is `3 xx 10^(8) m s^(-1)`.

Answer 1

We know that:
Refractive index of glasss`= ("Speed of light in air or vacum")/("Speed of light in glass")`
So, `1.50=(3 xx 10^(8))/("Speed of light in glass")`
or Speed of light in glass `=(3 xx 10^(8))/(1.50) ms^(-1)`
`=2 xx 10^(8) ms^(-1)`
Thus, the speed of light in glass is `2 xx 10^(8) ms^(-1)` or `(2 xx 10^(8)m//s)`