Question

Suppose the glass paperweight has index of refraction n=1.38. a) find the value of θ for which the reflection on the vertical surface of the paperweight exactly satisfies the condition for total internal reflection. b) If θ is increased, is the reflection at the vertical surface still total?

Answer 1

Answer:

a)θ=71.89°

b)NO

Explanation:

Given that

For glass n= 1.38

We know that for air n'=1

The angle  for total internal reflection θc given as

sin θc=n'/n

By putting the values

sin θc=n'/n

sin θc=1/1.38

θc=46.43°

n'sinθ = n sinθref

sinθref = cosθc

n'sinθ =  n cosθc

1 x sinθ =1.38 x cos 46.43°

θ=71.89°

b)

NO