YDSE in Water

Q. In a Young’s double slit experiment, the fringe width is found to be 0.4 mm. To make things more interesting, if the whole apparatus is immersed in water of refractive index $\frac{4}{3}$ without disturbing the geometrical arrangement, the new fringe width will be:

1. 0.30 mm
2. 0.40 mm
3. 0.53 mm
4. 0.50 micron

Q. In a Young’s double slit experiment, the fringe width is found to be 0.4 mm. To make things more interesting, if the whole apparatus is immersed in water of refractive index $\frac{4}{3}$ without disturbing the geometrical arrangement, the new fringe width will be:

1. 0.30 mm
2. 0.40 mm
3. 0.53 mm
4. 0.50 micron

Q. Two sources are placed on x- axis at a separation $d=3\lambda$. An observer starts moving from A on a circular track of radius $R(R>>d)$. How many bright points and dark points will he observe? Find the angular positions of maxima and minima.

1. Total No. of bright spots and dark spots are 12.
2. Total No. of bright spots and dark spots are 3.
3. Angular position of maxima is $\frac{\pi r}{6}$.
4. Angular position of minima is $\frac{\pi r}{12}$.

Q.

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

1. 2 cm, 7.5 cm

2. 3 cm, 6 cm

3. 2 cm, 4 cm

4. $\frac{4}{3}cm,103cm$

Q. In a YDSE performed with wavelength $\lambda =5890\dot{A}$, the angular fringe width is ${0.40}^{\circ }$. What is the angular fringe width if the entire set - up is immersed in water ? $(\mu =\frac{4}{3})$

1. ${0.15}^{\circ }$
2. ${0.30}^{\circ }$
3. ${0.40}^{\circ }$
4. ${0.50}^{\circ }$

Q. The fringe width in air, in Young's experiment is 3.6mm for light of $\lambda =6000\dot{A}$. If the arrangement is immersed in a transparent liquid of $\mu =1.2$ the fringe width would be

1. 4.32mm
2. 3mm
3. 0.33mm
4. 1.8mm