In the given figure and are two coherent sources oscillating in phase. The total number of bright fringes and their shape as seen on the large screen will be:
1. | 3, rectangular strips |
2. | 3, circular |
3. | 4, rectangular strips |
4. | 4, circular |
Two polaroids are kept crossed to each other. Now one of them is rotated through an angle of . The percentage of incident light now transmitted through the system is:
1. 15%
2. 25%
3. 50%
4. 60%
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.
Two superposing waves are represented by the following equations:
\({\mathrm{y}_1=5 \sin 2 \pi(10 \mathrm{t}-0.1 \mathrm{x}), \mathrm{y}_2=10 \sin 2 \pi(10 \mathrm{t}-0.1 \mathrm{x}).}\)
Ratio of intensities will be:
1. 1
2. 9
3. 4
4. 16
In Young's double-slit experiment, the ratio of intensities of bright and dark fringes is 9. This means that:
1. | the intensities of individual sources are 5 and 4 units respectively. |
2. | the intensities of individual sources are 4 and 1 unit respectively. |
3. | the ratio of their amplitudes is 3. |
4. | the ratio of their amplitudes is 6. |
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.