ABO Ophthalmology Complete Practice Exam 2025

When light passes through a prism, it is bent toward the base of the prism due to the phenomenon of refraction. As light enters the prism, it slows down as it moves from air (a medium of lower density) into the denser material of the prism. This change in speed causes the light to bend toward the normal line (an imaginary line perpendicular to the surface at the point of incidence).

In a prism, the apex is the top point, and the base is the bottom edge. When light exits the prism, it encounters a similar situation: it speeds up again and bends away from the normal, resulting in the overall direction of bending being toward the base of the prism. The unique shape of the prism causes the angles of incidence and refraction to lead light towards the base.

Therefore, when considering how light behaves in this situation, it is important to recognize that the configuration of the prism causes the light to bend toward the base as a consequence of the laws of refraction. This understanding is crucial in optics and helps explain the principles behind optical devices that utilize prisms.