## Question

The refractive indices of the material of a lens for violet, yellow and red colours of light are respectively 1.66, 1.64 and 1.62. The mean focal length of the lens is 10 cm. Determine the chromatic aberration of the lens between the violet and the red colours.

### Solution

0.625 cm

Let ω be the dispersive power of the material of the lens. Then the chromatic aberration between violet and red colours is given by

#### SIMILAR QUESTIONS

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