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प्रश्न
Observe the given figure and answer the following questions.

- Which colour light rays bend most?
- Which colour light rays bend least.
- What is the wavelength of violet light rays?
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उत्तर
- Violet coloured light rays bend the most.
- Red coloured light rays bend the least.
- The wavelength of violet light is close to 400 nm.
संबंधित प्रश्न
The path of a ray of light passing through a glass prism is shown below:

In this diagram, the angle of prism, angle of incidence, angle of emergence and angle of deviation, respectively, have been represented by:
(A) O, Y, Z and N,
(B) P, Y, M and Z,
(C) O, X, M and Z,
(D) P, X, Z and N.
What is spectrum?
The colour of white light which suffers the maximum bending (or maximum refraction) on passing through a glass prism is:
(a) yellow
(b) orange
(c) red
(d) violet
Which of the following colour of white light has the least wavelength?
(a) red
(b) orange
(c) violet
(d) blue
Which is optically denser: water or air? Give reason
Out of air and glass, which is optically rarer? Give reason.
Define the term dispersion of light.
- A beam of monochromatic light undergoes minimum deviation through an equiangular prism, how does the beam pass through the prism, with respect to its base?
- If white light is used in the same way as in part (a) above, what change do you expect in the emergent beam?
- What conclusion do you draw about the nature of white light in part (b)?
A glass prism is able to produce the spectrum when white light passes through it, but a glass slab doesn’t produce any spectrum. Explain why it is so.
Refer to fig
(i) Name the lens L.
(ii) What are the points O, O' called?
(iii) Complete the diagram to form the image of the object AB.
(iv) Write three characteristics of the image.

If white light is used in same way what change is expected in the emergent beam?
An object is placed in front of a converging lens and in front of a diverging lens as in fig.

(a)Complete the ray diagram to obtain an image.
(b)Compare the nature of image formed by both the lenses in the above case.
Draw a labelled diagram: Dispersion of light through a prism.
Sunlight entering through a narrow aperture falls on a prism. Draw a neat labelled ray diagram to show the formation of the spectrum on a screen. Name the colour obtained nearer the base of the prism.
In the figure, a beam of light consisting of three colours blue, red, and yellow is incident on a prism and on a rectangular glass block respectively. Complete the diagram by drawings of the refracted and emergent rays.

Say TRUE or FALSE
After passing through a prism, white light splits into a band of seven colours
Which of the following is a natural phenomenon which is caused by the dispersion of sunlight in the sky?
Which one of the following is involved for the formation of rainbow in the sky?
When sunlight passes through water droplets in the atmosphere it gets dispersed into its constituent colours forming a rainbow. A similar phenomenon is observed when white light passes through a prism.
Instead of sunlight, a green-coloured ray is passed through a glass prism. What will be the colour of the emergent ray?
