Q16DQ

Question

The focal length of a simple lens depends on the color (wavelength) of light passing through it. Why? Is it possible for a lens to have a positive focal length for some colors and negative for others? Explain.

Step-by-Step Solution

Verified
Answer

NO, it is not possible.

1Step 1: Definition of Focal length

The term focal length may be defined as the distance between the center of mirror and its focus.

2Step 2: Explain reason of question

The refractive index of the glass related to the light beam in the glass.depend on the wavelength so on different angles different color are appears. For n > 1 and one type of lens the sign of focal length is same. 


Hence, it is not possible for a lens to have a positive focal length for some colors and negative for others.