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प्रश्न
Which is refracted most by a prism : red light or violet light? Explain why?
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उत्तर
Violet light is refracted the most by a prism. When white light passes through a glass prism, violet colour has the minimum speed and a short wavelength. As violet has a short wavelength, it undergoes the maximum deviation and hence appears at the bottom of the spectrum. On the other hand, red light, which is also a part of the spectrum, has the maximum speed and a longer wavelength, and hence it is the least deviated and forms the upper part of the spectrum.
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संबंधित प्रश्न
In the formation of spectrum of white light by a prism:
which colour is deviated most?
Draw a diagram to show how white light can be dispersed into a spectrum by using a glass prism. Mark the various colours of the spectrum.
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 is least deviated by the prism?
(a) green
(b) violet
(c) indigo
(d) yellow
Out of the following, the colour of light having the maximum wavelength is:
(a) violet
(b) indigo
(c) green
(d) orange
A ray of light moving from an optically rarer to a denser medium
Explain briefly, with the help of a neat labelled diagram, how white light gets dispersed by a prism. On which surface of a prism, there is both dispersion and deviation of light, and on which surface of the prism, there is only deviation of light ?
What conclusion do you draw about the nature of white light in part (b)?
A ray of white light is passed through a glass prism and a spectrum is obtained on a screen.
- Name the seven colours of the spectrum in order.
- Do the colours have the same width in the spectrum?
- Which of the colour of the spectrum of white light deviates (i) the most, (ii) the least?
In the spectrum of white light by a prism, the colour at the extreme end opposite to the base of prism is ______.
When we place a glass prism in the path of a narrow beam of white light a spectrum is obtained. What happens when a second identical prism is placed in an inverted position with respect to the first prism? Draw a labelled ray diagram to illustrate it.
An object AB is placed in front of a convex lens as shown in fig. 4. Complete the ray diagram and obtain the image formed and state the nature of the image.
Make the correct choice for each of the following:
Which one of the following Fig correctly shows the path of the ray through the glass block?
Write the range of wavelength of the ultraviolet spectrum.
Write an Explanation.
Critical angle
Say TRUE or FALSE
Rainbow is formed by dispersion of which light by water drops
Assertion: We can see the rainbow in the sky when the rain starts falling after a spell of bright sunlight.
Reason: The rainbow is formed due to the dispersion of light.
What is a rainbow?
The dispersive powers of flint glass and crown glass are 0.053 and 0.034, respectively and their mean refractive indices are 1.68 and 1.53 for white light. Calculate the angle of the flint glass prism required to form an achromatic combination with a crown glass prism of refracting angle 4°:
Observe the given diagram and answer the questions:
- Name the process shown in the figure.
- Name the colour that deviates the most.
- Name the colour that deviates the least.
- Name any one phenomenon in nature which is based on the above process.
- Define ‘spectrum’.
