White light is passed through a double slit

PHYSICS · Single correct · CBSE · Physics · Wave Optics · Wave Optics

Problem

White light is passed through a double slit, and an interference pattern is observed on a screen

2.5\,\text{m}

away. The separation between the slits is

0.5\,\text{mm}

. The first violet and red fringes are formed

2.0\,\text{mm}

and

3.5\,\text{mm}

away from the central white fringe. Calculate the wavelengths of the violet and red light. (1)

400\,\text{nm},\ 650\,\text{nm}

(2)

400\,\text{nm},\ 700\,\text{nm}

(3)

350\,\text{nm},\ 200\,\text{nm}

(4)

200\,\text{nm},\ 350\,\text{nm}