Advertisements
Advertisements
प्रश्न
Write two points of difference between the phenomena of interference and diffraction.
Advertisements
उत्तर
| Interference | Diffraction | |
| 1 | Interference is the phenomenon of waves where waves from two different coherent sources superimpose at a given point and creates fringes. |
The phenomenon of bending of light around the corners of an opaque object which obstructs the path of light is called diffraction. |
| 2 | In interference pattern the intensity of dark fringe is completely zero. | In diffraction pattern the intensity of secondary minima is minimum, but not completely zero. |
| 3 | In interference pattern the width of all the interference fringes is equal. | In diffraction pattern the width of central maxima is large, and on increasing distance, the width of maxima decreases. |
| 4 | In interference pattern the intensity of all the bright bands is equal. | In diffraction pattern the intensity of all the secondary maxima is not equal. |
APPEARS IN
संबंधित प्रश्न
Describe briefly using a diagram how sunlight is polarised ?
A thin lens is made with a material having refractive index
\[\mu = 1 \cdot 5\]. Both the side are convex. It is dipped in water \[\mu = 1 \cdot 33\]. It will behave like
A convex lens is made of a material having refractive index
\[1 \cdot 2\] Both the surfaces of the lens are convex. If it is dipped into water (μ = 1.33), it will behave like
A 1 cm object is placed perpendicular to the principal axis of a convex mirror of focal length 7.5 cm. Find its distance from the mirror if the image formed is 0.6 cm in size.
A paperweight in the form of a hemisphere of radius 3.0 cm is used to hold down a printed page. An observer looks at the page vertically through the paperweight. At what height above the page will the printed letters near the centre appear to the observer?
Answer the following question in detail.
Explain the formation of a secondary rainbow. For which angular range with the horizontal is it visible?
Rainbow is the phenomenon due to ______.
| Case study: Mirage in deserts |
 |
|
To a distant observer, the light appears to be coming from somewhere below the ground. The observer naturally assumes that light is being reflected from the ground, say, by a pool of water near the tall object. Such inverted images of distant tall objects cause an optical illusion to the observer. This phenomenon is called mirage. This type of mirage is especially common in hot deserts. Based on the above facts, answer the following question: |
Which of the following phenomena is prominently involved in the formation of mirage in deserts?
| Case study: Mirage in deserts |
|
|
To a distant observer, the light appears to be coming from somewhere below the ground. The observer naturally assumes that light is being reflected from the ground, say, by a pool of water near the tall object. Such inverted images of distant tall objects cause an optical illusion to the observer. This phenomenon is called mirage. This type of mirage is especially common in hot deserts. Based on the above facts, answer the following question: |
The following figure shows a cross-section of a ‘light pipe’ made of a glass fiber of refractive index 1.68. The outer covering of the pipe is made of a material of refractive index 1.44. What is the range of the angles of the incident rays with the axis of the pipe for the following phenomena to occur.
Between the primary and secondary rainbows, there is a dark band known as Alexandar’s dark band. This is because ______.
- light scattered into this region interfere destructively.
- there is no light scattered into this region.
- light is absorbed in this region.
- angle made at the eye by the scattered rays with respect to the incident light of the sun lies between approximately 42° and 50°.
