Question

For 589-nm light, calculate the critical angle for the following materials surrounded by air. (a) fluorite (n = 1.434) ° (b) crown glass (n = 1.52) ° (c) ice (n = 1.309)

Answer 1

a) θc = 44.21⁰.

b) θc = 41.14⁰

c) θc = 40.36⁰

Step-by-step explanation:

sin θ =
`(n_2)/(n_1)`

For air,

n₂ = 1

so,

sin θ =
`(1)/(n_1)`

(a) fluorite : n₁ = 1.434⁰

sin θ = 0.697 θc = 44.21⁰.

(b) crown glass: n₁ = 1.52⁰

sin θ = 0.657 θc = 41.14⁰.

(c) sodium chloride : n₁= 1.544⁰

sin θ = 0.647 θc = 40.36⁰.