Question

According to the first law of refraction, the incident ray, the refracted ray, and the normal at the point of incidence:

Options

• are always collinear

• all lie in the same plane

• are mutually perpendicular

• all lie in different planes

Answer 1

The first law of refraction states that the incident ray, the refracted ray, and the normal at the point of incidence all lie in the same plane.