Advertisements
Advertisements
Question
Fill in the blank:
Very fine particles mainly scatter ………… colored light.
Advertisements
Solution
Very fine particles mainly scatter blue colored light.
APPEARS IN
RELATED QUESTIONS
Name the phenomenon responsible for it.
A parallel beam of light is incident on a converging lens parallel to its principal axis. As one moves away from the lens on the other side on its principal axis, the intensity of light
A concave mirror forms an image of 20 cm high object on a screen placed 5.0 m away from the mirror. The height of the image is 50 cm. Find the focal length of the mirror and the distance between the mirror and the object.
A concave mirror has a focal length of 20 cm. Find the position or positions of an object for which the image-size is double of the object-size.
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 3 cm tall object is placed at a distance of 7.5 cm from a convex mirror of focal length 6 cm. Find the location, size and nature of the image.
A converging mirror M1, a point source S and a diverging mirror M2 are arranged as shown in figure. The source is placed at a distance of 30 cm from M1. The focal length of each of the mirrors is 20 cm. Consider only the images formed by a maximum of two reflections. It is found that one image is formed on the source itself. (a) Find the distance between the two mirrors. (b) Find the location of the image formed by the single reflection from M2.

Locate the image of the point P as seen by the eye in the figure.

An optical fibre (μ = 1.72) is surrounded by a glass coating (μ = 1.50). Find the critical angle for total internal reflection at the fibre-glass interface.
A point source is placed at a depth h below the surface of water (refractive index = μ). (a) Show that light escapes through a circular area on the water surface with its centre directly above the point source. (b) Find the angle subtended by a radius of the area on the source.
The diameter of the sun is 1.4 × 109 m and its distance from the earth is 1.5 × 1011 m. Find the radius of the image of the sun formed by a lens of focal length 20 cm.
Explain: ‘How is a rainbow formed’?
Answer the following question in detail.
Explain the formation of a primary rainbow. For which angular range with the horizontal is it visible?
Answer the following question in detail.
Is it possible to see primary and secondary rainbow simultaneously? Under what conditions?
State any one difference between a primary rainbow and a secondary rainbow.
| 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.

The sky would appear red instead of blue if
A passenger in an aeroplane shall ______.

