Two non-coherent sources emit a light beam of intensities I and 4I. The maximum and minimum intensities in the resulting beam are: 

1. 9l and l

2. 9l and 3l

3. 5l and l

4. there is no interference, the intensity is 5I everywhere

In Young's double-slit experiment, the distance of the nth dark fringe from the centre is:

1. $n\left(\frac{\lambda D}{2d}\right)$

2. $n\left(\frac{2d}{\lambda D}\right)$

3. $(2n-1)\frac{\lambda D}{2d}$

4. $(2n-1)\frac{4d}{\lambda D}$

If the path difference between the interfering waves is, $n\lambda$ then the fringes obtained on the screen will be:

1. Dark

2. Bright

3. colored

4. White

The fringe width in a Young's double-slit experiment can be increased. If we decrease:

1. Width of the slits

2. Separation of the slits

3. The wavelength of the light used

4. Distance between slits and screen

In a YDSE, the central bright fringe can be identified.

1. as it has a greater intensity than the other bright fringes

2. as it is wider than the other bright fringes

3. as it is narrower than the other bright fringes

4. by using white light instead of single-wavelength light

If Young's double-slit experiment is performed with white light, then which of the following is not true?

1. the central maximum will be white

2. there will not be a completely dark fringe

3. the fringe next to the central will be red

4. the fringe next to the central will be violet

In Young's double-slit experiment, the interference pattern is observed on the screen L distance apart from slits, the average distance between adjacent fringes is x and slits separation is d, then the wavelength of light will be:

1. xd/L

2. xL/d

3. Ld/x

4. Ldx

Light of wavelength $\lambda$ in air enters a medium of refractive index $\mu$. Two points in this medium, lying along the path of this light, are at a distance x apart. The phase difference between these points is:

1. $\frac{2\mathrm{\pi \mu x}}{\lambda }$

2. $\frac{2\mathrm{\pi x}}{\mu \lambda }$

3. $\frac{2\mathrm{\pi }(\mathrm{\mu }-1)\mathrm{x}}{\lambda }$

4. $\frac{2\mathrm{\pi x}}{(\mu -1)\lambda }$

The ratio of the intensity at the centre of a bright fringe to the intensity at a point one-quarter of the fringe width from the centre is:

1. 2

2. 1/2

3. 4

4. 16

In Young's double-slit interference experiment, if the slit separation is made threefold, the fringe width becomes:

1. sixfold

2. threefold

3. 3/6 fold

4. 1/3 fold