Where do light rays cross after passing through a converging lens?

Where do light rays cross after passing through a converging lens?

• A. Normal line
• B. Index of refraction
• C. Angle of reflection
• D. Focal point

Answer: (D)

When light passes through a converging lens, parallel rays bend toward the optical axis and meet at a single point on the opposite side. That meeting point is the focal point, a specific location along the axis where rays from objects at infinity converge after refraction. The other terms don’t describe this behavior: the normal line is just a surface-perpendicular reference, the index of refraction is a property of the material, and the angle of reflection relates to bouncing off a surface rather than where refracted rays cross.

When light passes through a converging lens, parallel rays bend toward the optical axis and meet at a single point on the opposite side. That meeting point is the focal point, a specific location along the axis where rays from objects at infinity converge after refraction. The other terms don’t describe this behavior: the normal line is just a surface-perpendicular reference, the index of refraction is a property of the material, and the angle of reflection relates to bouncing off a surface rather than where refracted rays cross.