In a prism, does light bend toward the apex or the base?

• A. Apex
• B. Base
• C. Center
• D. Along the optical axis

Answer: (B)

Light is refracted twice as it passes through a prism. With the typical triangular orientation, those two refractions steer the ray so that the net deviation is toward the base—the thicker side opposite the apex. The base is the direction toward which the light is redirected after exiting the prism, whereas the apex or moving along the optical axis isn’t the resulting path in this standard setup. So, light bends toward the base.