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प्रश्न
What is a rainbow? What are the two conditions necessary for the formation of a rainbow in the sky?
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उत्तर
A rainbow is a natural spectrum of seven colours formed in the sky when the water droplets in the atmosphere cause the dispersion of sunlight. The two conditions necessary for the formation of a rainbow are as follows.
1. The sun should be shining.
2. It should be raining.
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संबंधित प्रश्न
Draw a ray diagram to explain the term angle of deviation.
Study the following ray diagram:

In this diagram, the angle of incidence, the angle of emergence and the angle of deviation respectively have been represented by
(A) y, p, z
(B) x, q, z
(C) p, y, z
(D) p, z, y
What happens when a ray of ordinary light is passed through a triangular glass prism?
What is spectrum? What is the name of glass shape used to produce a spectrum?
In the figure given alongside, a narrow beam of white light is shown to pass through a triangular glass prism. After passing through the prism, it produces a spectrum YX on the screen.
Why do different colours of white light bend through different angles with respect to the incident beam of light?
A beam of white light is shone onto a glass prism. The light cannot be:
(a) deviated
(b) dispersed
(c) focused
(d) refracted
Which of the following colour of white light has the least wavelength?
(a) red
(b) orange
(c) violet
(d) blue
When a white light ray falls on a prism, the ray at its first surface suffers ______.
The frequency range of visible light is from 3.75 × 1014 Hz to 7.5 × 1014 Hz. Calculate its wavelength range. Take speed of light = 3 × 108 m/s.
In the following diagram, the correctly marked angles are
(A) All
(B) Only ∠i and ∠A
(C) ∠i, ∠r and ∠A
(D) ∠i, ∠A and ∠D
While performing the experiment to trace the path of a ray of light passing through a glass prism, four students marked the incident ray and the emergent ray in their diagrams in the manner shown below. 
(A) I
(B) II
(C) III
(D) IV
If a monochromatic beam of light undergoes minimum deviation through an equiangular prism, how does the beam pass through the prism, with respect to its base?
Complete the ray diagram given below to show the nature of light produced on the screen.
The completed ray diagram is as shown below:

A wave has wavelength 50Å of State the speed in vacuum.
A wave has wavelength 50Å of State its one use.
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.
Rainbow is a beautiful natural phenomenon. It is the combined effect of a natural three processes together produced by light. Write it into the circle.


Which of the following is a natural phenomenon which is caused by the dispersion of sunlight in the sky?
The angle of deviation through a prism is minimum when

- Incident rays and emergent rays are symmetric to the prism.
- The refracted ray inside the prism becomes parallel to its base.
- The angle of incidence is equal to that of the angle of emergence.
- When the angle of emergence has doubled the angle of incidence.
Choose the correct answer from the options given below:
