Question

A ray in glass (n = 1.51) reaches a boundary with air at 49.2 deg. Does it reflect internally or refract into the air? Enter 0 for reflect, and 1 for refract.

Answer 1

Answer:

0 - Then, the ray is totally reflected

Explanation:

The ray reaches the boundary between the two mediums at 49.2°.

If the ray is totally reflected it is necessary that the crictical angle is lower that the incidet angle.

You use the following to calculate the critical angle:

$\theta_c=sin^{-1}(\frac{n_2}{n_1})$       (1)

n2: index of refraction of the second medium (air) = 1.00

n1: index of refraction of the first medium (glass) = 1.51

You replace the values of the parameters in the equation (1):

$\theta_c=sin^{-1}(\frac{1.00}{1.51})=41.47\°$

The critical angle is 41.47°, which is lower than the incident angle 49.2°.

Then, the ray is totally reflected.

0