Advertisements
Advertisements
प्रश्न
For light diverging from a point source ______.
- the wavefront is spherical.
- the intensity decreases in proportion to the distance squared.
- the wavefront is parabolic.
- the intensity at the wavefront does not depend on the distance.
पर्याय
a and b
a and c
b and c
c and d
Advertisements
उत्तर
a and b
Explanation:
| Type of wavefront | Intensity | Amplitude |
Spherical |
`I oo 1/r^2` | `A oo 1/r` |
Cylindrical |
`I oo 1/r` | `A oo 1/sqrt(r)` |
Plane |
`I oo 1/r^0` | `A oo r^0` |
Due to the point source light propagates in all directions symmetrically and hence, wavefront will be spherical as shown in the diagram.
As intensity of the source will be `I oo 1/r^2`
Where r is radius of the wavefront at any time.
Hence the intensity decreases in proportion to the distance squared.
APPEARS IN
संबंधित प्रश्न
On the basis of Huygens' wave theory of light prove that velocity of light in a rarer medium is greater than velocity of light in a denser medium.
Explain the construction of plane wavefront using Huygens’ principle.
What is the shape of the wavefront in the following case?
The portion of the wavefront of light from a distant star was intercepted by the Earth.
Use Huygens' principle to verify the laws of refraction.
The refractive indices of water and diamond are `4/3` and 2.42 respectively. Find the speed of light in water and diamond. (c = 3x108 m/s)
Using this principle draw a diagram to show how a plane wave front incident at the interface of the two media gets refracted when it propagates from a rarer to a denser medium. Hence verify Snell's law of refraction.
Derive the law of reflection using Huygen’s Wave Theory.
A plane wave front AB propagating from denser medium (1) into a rarer medium (2) is incident on the surface P1P2 separating the two media as shown in fig.
Using Huygen’s principle, draw the secondary wavelets and obtain the refracted wave front in the diagram.
Relation between ray and wavefront is ______.
Answer the following question briefly and to the point:
What is the phase difference between any two points lying on the same wavefront?
The inverse square law of intensity is valid for a
Huygen's conception of secondary waves ______.
Figure shows a standard two slit arrangement with slits S1, S2, P1, P2 are the two minima points on either side of P (Figure). At P2 on the screen, there is a hole and behind P2 is a second 2-slit arrangement with slits S3, S4 and a second screen behind them.
Is Huygen’s principle valid for longitudinal sound waves?
What is the shape of the wavefront on earth for sunlight?
According to Huygens’s principle, the amplitude of secondary wavelets is ______.
Represent diagrammatically how the incident planar wavefronts of wavelength λ pass through an aperture of size d, when d is approximately equal to λ.
