The angle of the incident for the light ray, in this case, is 49.4459°. Considering the refractive index of air and glass as 1.000273 and 1.52, respectively. Such that, sin(theta1) = sin(theta2) × n2 / n1 = = sin(30°) × 1.52 / 1.000273 = 49.4459°.
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