Two sources with intensity I_o and 4I_o respectively interfere at a point in a medium. The maximum and the minimum possible intensity respectively would be:
1. 2I_o, I_o
2. 9I_o, 2I_o
3. 4I_o, I_o
4. 9I_o, I_o

The relation between the fringe width for the red light and yellow light is: (all other things being the same.)

$1. {\beta }_{red}<{\beta }_{yellow}$
$2. {\beta }_{red}>{\beta }_{yellow}$
$3. {\beta }_{red}={\beta }_{yellow}$
$4. {\beta }_{red}=2{\beta }_{yellow}$

Fringe width in a particular YDSE is measured to be $\beta$. What will be the fringe width if the wavelength of the light is doubled, the separation between the slits is halved and the separation between the screen and slits is tripled?

1. 10 times

2. 11 times

3. Same

4. 12 times

The first diffraction minima due to a single slit diffraction is at $\mathrm{\theta } = 30°$for a light of wavelength  \(5000~\mathring A.\)  The width of the slit is:

1. 5 x 10^-5 cm

2. 10 x 10^-5 cm

3. 2.5 x 10^-5 cm

4. 1.25 x 10^-5 cm

A plane-polarized light with intensity \(I_0\) is incident on a polaroid with an electric field vector making an angle of \(60^{\circ}\) with the transmission axis of the polaroid. The intensity of the resulting light will be:
1. \(\frac{I_0}{4}\)
2. \(I_0\)
3. \(2I_0\)
4. \(\frac{I_0}{2}\)

If the light is polarised by reflection, then the angle between reflected and refracted light is:

1. $\pi$

2. $\pi$/2

3. 2$\pi$

4. $\pi$/4

Which of the following is not true?

When the light diverges from a point source, the shape of the wavefront is:

1. Parabolic.

2. Plane.

3. Spherical.

4. Elliptical.

What will be the angular width of central maxima in Fraunhofer diffraction when the light of wavelength \(6000~\mathring A\) is used and slit width is $12\times {10}^{-5}\mathrm{cm}$?

1. 2 rad

2. 3 rad

3. 1 rad

4. 8 rad

Red light is generally used to observe diffraction patterns from a single slit. If the blue light is used instead of red light, then the diffraction pattern: