Question

For the given incident ray as shown in figure, the condition of total internal reflection of this ray the minimum refractive index of prism will be : - 45º incident ray

Answer 1

BE more than critical angle, ie, Θ>c see diagram, ∠r + ∠ Θ =90° sini/sinr =μ ,ie sin 45/ sin r= μ sinr= 1/ μ√2 Θ> c, ie, sinΘ> sin c sin90-r > 1/μ cosr >1/μ √1-sin^2(r) >1/μ 1- 1/2μ^2 > 1/μ^2 1 > 1/2μ^2 + 1/μ^2 μ^2 > 3/2

Answer 2

Answer:

I tried this question  and got it in the simplest way ......the and is the 3rd opt ie . Root 3/2........also we can easily eliminate the rest options as they don't make much sense

Explanation: