## Question

The refractive indices of the material of a lens for violet and red colours are 1.56 and 1.54 respectively. If the focal length of the lens for violet light is 40 cm, then calculate (i) focal length of the lens for red light. (ii) Longitudinal chromatic aberration of the lens and (iii) Dispersive power of the material of the lens.

### Solution

41.48 cm, 1.48 cm, 0.036

(ii) The longitudinal chromatic aberration is

(iii) The dispersive power is

#### SIMILAR QUESTIONS

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