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. | \(\dfrac{3\pi}{2}\) | 4. | \(\dfrac{\pi}{2}\) |
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. \(0^{\circ}<i_b<30^{\circ}\)
1. | half | 2. | four times |
3. | one-fourth | 4. | double |
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
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 angular width of the central maximum in the Fraunhofer diffraction for \(\lambda=6000~{\mathring{A}}\) is \(\theta_0\). When the same slit is illuminated by another monochromatic light, the angular width decreases by \(30\%\). The wavelength of this light is:
1. \(1800~{\mathring{A}}\)
2. \(4200~{\mathring{A}}\)
3. \(420~{\mathring{A}}\)
4. \(6000~{\mathring{A}}\)