With a certain double-slit set-up

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

Problem

With a certain double-slit set-up, the fringe width is

3.0\,\text{mm}

in air. When the entire arrangement is immersed in an oil, the fringe width reduces to

2.0\,\text{mm}

. What is the refractive index of the oil? (a)

1.67

(b)

1.50

(c)

1.33

(d)

2.25