1. | its wavelength and frequency both increase. |
2. | its wavelength increases but frequency remains unchanged. |
3. | its wavelength decreases but frequency remains unchanged. |
4. | its wavelength and frequency both decrease. |
When light is refracted, which of the following does not change?
1. wavelength
2. frequency
3. velocity
4. amplitude
The wavefronts of a light wave travelling in vacuum are given by \(x+y+z=c\). The angle made by the direction of propagation of light with the X-axis is:
1. \(0^{\circ}\)
2. \(45^{\circ}\)
3. \(90^{\circ}\)
4. \(\mathrm{cos^{-1}\left(\frac{1}{\sqrt{3}}\right )}\)
The wavefronts of light coming from a distant source of unknown shape are nearly:
1. plane
2. elliptical
3. cylindrical
4. spherical
The inverse square law of intensity (i.e., the intensity \(\propto \frac{1}{r^2}\)) is valid for:
1. a point source
2. a line source
3. a plane source
4. a cylindrical source
A light wave can travel:
(a) | in vacuum |
(b) | in vacuum only |
(c) | in a material medium |
(d) | in a material medium only |
Choose the correct option:
1. (a) and (b)
2. (b) and (c)
3. (a) and (c)
4. (c) and (d)
Huygens' principle of secondary wavelets may be used to:
(a) | find the velocity of light in a vacuum. |
(b) | explain the particle behaviour of light. |
(c) | find the new position of a wavefront. |
(d) | explain Snell's law. |
Choose the correct option:
1. (a) and (b)
2. (b) and (c)
3. (c) and (d)
4. All of these
Light waves travel in vacuum along the X-axis. Which of the following may represent the wavefronts?
1. \(x=c\)
2. \(y=c\)
3. \(z=c\)
4. \(x+y+z=c\)