In Young's double-slit experiment using the light of wavelength \(\lambda\), \(60\) fringes are seen on a screen. If the wavelength of light is decreased by \(50\%\), then the number of fringes on the same screen will be:
1. \(30\)
2. \(60\)
3. \(120\)
4. \(90\)
1. | \(\dfrac{1}{\sqrt{3}}\) | 2. | \(\dfrac{3}{2}\) |
3. | \(\sqrt{3}\) | 4. | \(\dfrac{\sqrt{3}}{2}\) |
Five identical polaroids are placed coaxially with \(45^{\circ}\) angular separation between pass axes of adjacent polaroids as shown in the figure. (\(I_0\): Intensity of unpolarized light)
The intensity of light, \(I\),
emerging out of the \(5\)th polaroid is:
1. | \(\dfrac{I_0}{4}\) | 2. | \(\dfrac{I_0}{8}\) |
3. | \(\dfrac{I_0}{16}\) | 4. | \(\dfrac{I_0}{32}\) |
In Young's double-slit experiment, the ratio of maximum intensity at a point to the intensity at the same point when one slit is closed, is:
1. \(2\)
2. \(3\)
3. \(4\)
4. \(1\)
Two light sources are said to be coherent when their:
1. | amplitudes are equal and have a constant phase difference. |
2. | wavelengths are equal. |
3. | intensities are equal. |
4. | frequencies are equal and have a constant phase difference. |
Which statement is true for interference?
1. | Two independent sources of light can produce interference pattern. |
2. | There is no violation of conservation of energy. |
3. | White light cannot produce interference. |
4. | The interference pattern can be obtained even if coherent sources are widely apart. |
Light waves of intensities \(I\) and \(9I\) interfere to produce a fringe pattern on a screen. The phase difference between the waves at point \(P\) is \(\frac{3\pi}{2}\) and \(2\pi\) at other point \(Q\). The ratio of intensities at \(P\) and \(Q\) is:
1. \(8:5\)
2. \(5:8\)
3. \(1:4\)
4. \(9:1\)
In Young's double-slit experiment sources of equal intensities are used.
The distance between the slits is \(d\) and the wavelength of light used is \(\lambda (\lambda<<d)\). The angular separation of nearest points on either side of central maximum where intensities become half of the maximum value is:
1. \(\frac{\lambda}{d}\)
2. \(\frac{\lambda}{2d}\)
3. \(\frac{\lambda}{4d}\)
4. \(\frac{\lambda}{6d}\)
Four coherent sources of intensity \(I\) are superimposed constructively at a point. The intensity at that point is:
1. \(4I\)
2. \(8I\)
3. \(16I\)
4. \(24I\)
Two waves, each of intensity \(i_{0}\)
1. | \(2i_{0}\) | 2. | \(i_{0}\) |
3. | \(i_{0}/2\) | 4. | zero |