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. |
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 |
A single slit of width 0.1 mm is illuminated by a parallel beam of light of wavelength 6000 and diffraction bands are observed on a screen 0.5 m from the slit. The distance of the third dark band from the central bright band is:
1. 3 mm
2. 9 mm
3. 4.5 mm
4. 1.5 mm
In Young's double-slit experiment the light emitted from the source has = 6.5 × 10–7 m and the distance between the two slits is 1 mm. The distance between the screen and slits is 1 metre. Distance between third dark and fifth bright fringe will be:
1. 3.2 mm
2. 1.63 mm
3. 0.585 mm
4. 2.31 mm
In Young's double-slit experiment, the slit separation is doubled. This results in:
1. | An increase in fringe intensity |
2. | A decrease in fringe intensity |
3. | Halving of the fringe spacing |
4. | Doubling of the fringe spacing |
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%
Light travels faster in the air than in glass. This is in accordance with:
1. | the wave theory of light. |
2. | the corpuscular theory of light. |
3. | neither (1) nor (2) |
4. | both (1) and (2) |
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