Two beams of light having intensities I and 4I interfere to produce a fringe pattern on a screen. The phase difference between the beams is n/2 at point A, n and at point B. Then the difference between the resultant intensities at A and B is :-

1. 2I

2. 4I

3. 5I

4. 7I

A laser beam is used for locating distant objects because :-

1. it is monchromatic

2. it is constant

3. it is not observed

4. it has small angular spread

In young's double slit experiment two disturbances arriving at a point P have phase difference of n/3. The intensity of this point experiment as a fraction of maximum intensity of this point expressed as a fraction of maximum intensity I₀ is :-

1. $\frac{3}{2}{\mathrm{I}}_0$

2. $\frac{1}{2}{\mathrm{I}}_0$

3. $\frac{4}{3}{\mathrm{I}}_0$

4. $\frac{3}{4}{\mathrm{I}}_0$

Two slits in young's double slit experiment have width in the ratio 81: 1 . The ratio of the amplitude of light waves is :

1. 3: 1

2. 3: 2

3. 9: 1

4. 6: 1

In young's double slit experiment using monochromatic light of wavelength $\mathrm{\lambda }$. The intensity of light at a point on the screen with path difference $\mathrm{\lambda }$ is M unit. The intensity of light at a point where path difference is $\mathrm{\lambda }$/3 is :-

1. M/2

2. M/4

3. M/8

4. M/8

Yellow light of wavelength 6000 $\stackrel{\circ }{\mathrm{A}}$ produces fringes of width 0.8 mm in young's double slit experiment. If the source is replaced by another monochromatic source of wavelength 7500 $\stackrel{\circ }{\mathrm{A}}$ and the seperation between the slits is doubled then the fringe width becomes :-

1. 0.1 mm

2. 0.5 mm

3. 4.3 mm

4. 1 mm

In young's double slit experiment the distance between the slits S₁ and S₂ is 1 mm. What should be the width of each slit be so as to obtain 10 maxima of the double slit pattern within the central maximum of the single slit pattern?

1. 0.9 mm

2. 0.8 mm

3. 0.2 mm

4. 0.6 mm

The intensity of the maxima and minima in an interference pattern produced by two coherent sources of light 9: 1 . The intensities of the used light sources are in ratio :-

1. 3: 1

2. 4: 1

3. 9: 1

4. 10: 1

In double slit experiment the angular width of a fringe is found to be 0.2^o on a screen placed 1 m away. The wavelength of light used is 600 nm. The angular width of the fringe if entire experimental apparatus is immersed in water is $\left({\mathrm{\mu }}_{\text{water }}=\frac{4}{3}\right)$ :-

1. 0.15^o

2. 1^o

3. 2^o

4. 0.3^o

In young's double slit experiment distance between two sources is 0.1 mm. The distance of screen from the source of 20 cm. Wavelength of light used is 5460 $\stackrel{\circ }{\mathrm{A}}$. Then, angular position of the first dark fringe is :-

1. 0.08^o

2. 0.16^o

3. 0.20^o

4. 0.31^o