If the ratio of amplitudes of two coherent sources producing an interference pattern is \(3:4\), the ratio of intensities at maxima and minima is:
1. \(3:4\)
2. \(9:16\)
3. \(49:1\)
4. \(25:7\)
Two coherent sources are \(0.3\) mm apart. They are \(1\) m away from the screen. The second dark fringe is at a distance of \(0.3\) cm from the center. The distance of the fourth bright fringe from the centre is:
1. \(0.6~\text{cm}\)
2. \(0.8~\text{cm}\)
3. \(1.2~\text{cm}\)
4. \(0.12~\text{cm}\)
Huygens' wave theory allows us to know the:
1. | Wavelength of the wave. |
2. | Velocity of the wave. |
3. | Amplitude of the wave. |
4. | Propagation of wavefront. |
In Young's double-slit experiment, an electron beam is used to obtain an interference pattern. If the speed of electrons is increased:
1. | No interference pattern will be observed. |
2. | Distance between two consecutive fringes remains the same. |
3. | Distance between two consecutive fringes will decrease. |
4. | Distance between two consecutive fringes will increase. |
Huygen's principle for secondary wavelets may be used to:
1. | explain Snell's law. |
2. | find the velocity of light in vacuum. |
3. | find a new position of a wavefront. |
4. | both (1) & (3) are correct. |
1. | \(I_0\) | 2. | \(\dfrac{I_0}{2}\) |
3. | \(\dfrac{I_0}{4}\) | 4. | \(\dfrac{I_0}{8}\) |
Young's double-slit experiment is performed in a liquid. The \(10\)th bright fringe in the liquid lies where the \(8\)th dark fringe lies in a vacuum. The refractive index of the liquid
is approximately:
1. \(1.81\)
2. \(1.67\)
3. \(1.54\)
4. \(1.33\)
If the \(5\)th order maxima of wavelength \(4000~\mathring{A}\) in Young's double-slit experiment coincides with the \(n\)th order maxima of wavelength \(5000~\mathring{A},\) then \(n\) is equal to:
1. \(5\)
2. \(8\)
3. \(4\)
4. \(10\)
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. \(24I\)
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. \(\frac{\lambda}{6d}\)