Question

In the figure, a light ray enters a glass slab at point A at incident angle θ₁ = 60.9^o and then undergoes total internal reflection at point B. What minimum value for the index of refraction of the glass can be inferred from this information? Assume that the index of refraction of air under standard temperature (0°C) and pressure (1 atm) is 1.00029.

Incident ray Air Glass B

Answer 1

81 using snell's law of refraction at A n, sind, = 12 sins 1x sin(60.9) = n sine n senr= sin 60-9 И. = cost O₂ = (90-r) sindz= singor) for TIR( total internal reflection 02>, oc where 0e - citial angle = sini? 4 (D) from equation (it) & (in) sende seniąc ta (N) - 2 cosr s No-sente - J-(sem to 9.)? h2 = n = 11.766 Refractive Index of glass slab must be greater than 1.33 1- 0.764 t - 0.764 n2 1-764-1 n2