Question

Which is TRUE about a concave

lens that causes the light to
refract?
A. It is a medium that speeds up light.
B. It is a medium that does not change the light.
C. It is a medium that slows down light.
D. It is a medium that absorbs light.

Answer 1

It is a medium that does not change the light. (B)

Answer 2

Answer: The correct answer is B. It is a medium that does not change the light.

Explanation: The concave lense affects the phase velocity, but not the speed of light. A lens's shape determines the images it forms. When parallel rays of light enter a concave lens, the light waves refract outward or spread out. The light rays refract twice: first when entering the lens and second when leaving the lens. Only the light rays passing through the center of the lens remain straight.