Focal length of convex lens will miximum for

Options

A. Red light
B. Blue light
C. Yellow light
D. Violet light

Answer

A

Explanation

`(1)/(f)=(n-1) ((1)/(R_(1))-(1)/(R_(2)))=K(n-1)`
Thus, `f prop (1)/(n)`.
`therefore f_(R ) gt f_(V)`
`therefore` f will be maximum for red light.