Two thin slabs of refractive indices `mu_(1)` and `mu_(2)` are placed parallel to each other in the x-z plane. If the direction of propagation of a ray in the two media are along the vectors `vec(r)_(1) = a hati +b hatj` and `vec(r)_(2) = c hati +d hatj` then we have:

Options

A. `(mu_(1)a)/sqrt(a^(2)+b^(2))= (mu_(2)c)/sqrt(c^(2)+d^(2))`
B. `mu_(1)a=mu_(2)b`
C. `mu_(1) (a^(2)+b^(2))=mu_(2) (c^(2)+d^(2))`
D. `mu_(1) b=mu_(2)a`

Answer

C