A beam of light AO is incident on a glass slab (μ = 1.54) in a direction as shown in the figure. The reflected ray OB is passed through a Nicol prism. On viewing through a Nicole prism, we find on rotating the prism that:
1. | the intensity is reduced down to zero and remains zero. |
2. | the intensity reduces down somewhat and rises again. |
3. | there is no change in intensity. |
4. | the intensity gradually reduces to zero and then again increases. |
Unpolarized light of intensity 32 Wm–2 passes through three polarizers such that the transmission axes of the first and second polarizer make an angle of 30° with each other and the transmission axis of the last polarizer is crossed with that of the first. The intensity of the final emerging light will be:
1. 32 Wm–2
2. 3 Wm–2
3. 8 Wm–2
4. 4 Wm–2
When an unpolarized light of intensity I0 is incident on a polarizing sheet, the intensity of the light which does not get transmitted is:
1. Zero
2. I0
3.
4.
On superposition of two waves \(y_{1}=3sin\left ( \omega t-kx \right )\) and \(y_{2}=4sin\left ( \omega t-kx+\frac{\pi }{2} \right )\) at a point, the amplitude of the resulting wave will be:
1. 7
2. 5
3.
4. 6.5
In Young's double-slit experiment using the light of wavelength '', 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
If the polarising angle for a material is , then the refractive index of the material will be:
1.
2.
3.
4.
Five identical polaroids are placed coaxially with \(45^{\circ}\) angular separation between pass axes of adjacent polaroids as shown in the figure. (I0: Intensity of unpolarized light)
The intensity of light, I,
emerging out of the 5th polaroid is:
1.
2.
3.
4.
In Y.D.S.E., 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. |