In Young's double slit experiment the y-coordinates of central maxima and 10th maxima are `2cm` and `5cm` respectively. When the YDSE apparatus is immersed in a liquid of refractive index `1.5` the corresponding y-coordintates will be

Options

A. `2cm, 7,5cm`
B. `3cm,6cm`
C. `4/3cm,10/3cm`
D. `2cm,4cm`

Answer

D

Explanation

Position of `10^(th)`maxima `=(10lambdaD)/d=3` cm (w.r. to central maxima)
`(lambdaD)/d=3/10cm`
New fringe width `=3/(10xxmu)`
New position of 10^(th)maxima`=3/(10xx1.5)xx10=2cm`
:. Position of central maxima `=2cm`
:. `10^(th)maxima = 4cm`