1. | \(\frac{I}{2}\) | 2. | \(\frac{I}{3}\) |
3. | \(\frac{3I}{4}\) | 4. | \(\frac{2I}{3}\) |
1. | angular separation of the fringes increases. |
2. | angular separation of the fringes decreases. |
3. | linear separation of the fringes increases. |
4. | linear separation of the fringes decreases. |
A monochromatic light of frequency \(500\) THz is incident on the slits of a Young's double slit experiment. If the distance between the slits is \(0.2\) mm and the screen is placed at a distance \(1\) m from the slits, the width of \(10\) fringes will be:
1. \(1.5\) mm
2. \(15\) mm
3. \(30\) mm
4. \(3\) mm
1. | \(60^\circ\) | 2. | \(75^\circ\) |
3. | \(30^\circ\) | 4. | \(45^\circ\) |
Statement I: | If screen is moved away from the plane of slits, angular separation of the fringes remains constant. |
Statement Ii: | If the monochromatic source is replaced by another monochromatic source of larger wavelength, the angular separation of fringes decreases. |
1. | Statement I is false but Statement II is true. |
2. | Both Statement I and Statement II are true. |
3. | Both Statement I and Statement II are false. |
4. | Statement I is true but Statement II is false. |
The interplanar distance in a crystal is \(2.8 \times 10^{-8} \) m. The value of the maximum wavelength which can be diffracted:
1. \(2.8 \times 10^{-8} \)
2. \(5.6 \times 10^{-8} \)
3. \(1.4 \times 10^{-8} \)
4. \(7.6 \times 10^{-8} \)
For a crystal with λ = 1 Å and Bragg's angle θ = 60°, the second-order diffraction, 'd' (distance between two consecutive atomic layers) will be:
1. 1.15 Å
2. 0.75 Å
3. 0.55 Å
4. 2.1 Å
Two coherent sources of light interfere and produce fringe patterns on a screen. For the central maximum, the phase difference between the two waves will be:
1. zero
2. \(\pi\)
3. \(\frac{3\pi}{2}\)
4. \(\frac{\pi}{2}\)
The Brewster's angle for an interface should be:
1. \(30^{\circ}<i_b<45^{\circ}\)
2. \(45^{\circ}<i_b<90^{\circ}\)
3. \(i_b=90^{\circ}\)
4. \(0^{\circ}<i_b<30^{\circ}\)