An unpolarised light incident on a polariser has amplitude \(A\), and the angle between analyzer and polariser is \(60^{\circ}\). The light transmitted by the analyzer has an amplitude of:
1. \(A\sqrt{2}\)
2. \(\frac{A}{2\sqrt{2}}\)
3. \(\frac{\sqrt{3}A}{2}\)
4. \(\frac{A}{2}\)
A parallel beam of monochromatic light of wavelength \(5000~\mathring{A}\) is incident normally on a single narrow slit of width \(0.001\) mm. The light is focused by a convex lens on a screen placed on the focal plane. The first minimum will be formed for the angle of diffraction equal to:
1. \(0^{\circ}\)
2. \(15^{\circ}\)
3. \(30^{\circ}\)
4. \(60^{\circ}\)
The direction of the first secondary maximum in the Fraunhofer diffraction pattern at a single slit is given by:
\((a\) is the width of the slit)
1. \(a\sin\theta = \frac{\lambda}{2}\)
2. \(a\cos\theta = \frac{3\lambda}{2}\)
3. \(a\sin\theta = \lambda\)
4. \(a\sin\theta = \frac{3\lambda}{2}\)
In Young's double slit experiment, the angular width of fringe is \(0.20^{\circ}\) for sodium light of wavelength \(5890~\mathring{A}\). The angular width of fringe, if the complete system is dipped in water, will be:
1. \(0.11^{\circ}\)
2. \(0.15^{\circ}\)
3. \(0.22^{\circ}\)
4. \(0.30^{\circ}\)
The slits in Young's double-slit experiment have equal widths and the source is placed symmetrically relative to the slits. The intensity at the central fringe is \(I_0\). If one of the slits is closed, the intensity at this point will be:
1. \(I_0\)
2. \(\frac{I_0}{4}\)
3. \(\frac{I_0}{2}\)
4. \(4I_0\)
In two separate set-ups of the Young's double slit experiment, fringes of equal width are observed when lights of wavelengths in the ratio \(1:2\) are used. If the ratio of the slit separation in the two cases is \(2:1\), the ratio of the distances between the plane of the slits and the screen in the two set-ups is:
1. \(4:1\)
2. \(1:1\)
3. \(1:4\)
4. \(2:1\)
In Young's experiment, light of wavelength \(4000~\mathring{A}\) is used to produce bright fringes of width \(0.6\) mm, at a distance of \(2\) meters. If the whole apparatus is dipped in a liquid of refractive index \(1.5\), then fringe width will be:
1. \(0.2~\text{mm}\)
2. \(0.3~\text{mm}\)
3. \(0.4~\text{mm}\)
4. \(1.2~\text{mm}\)
If an interference pattern has maximum and minimum intensities in a \(36:1\) ratio, then what will be
the ratio of their amplitudes?
1. \(5:7\)
2. \(7:4\)
3. \(4:7\)
4. \(7:5\)
Which of the following statements indicates that light waves are transverse?
1. | Light waves can travel in a vacuum. |
2. | Light waves show interference. |
3. | Light waves can be polarized. |
4. | Light waves can be diffracted. |
Soap bubble appears coloured due to the phenomenon of:
1. Interference
2. Diffraction
3. Dispersion
4. Reflection