Advertisements
Advertisements
प्रश्न
How could you show that the colours of the spectrum combine to give white light?
Advertisements
उत्तर
We know that a spectrum of colours is formed when a beam of white light is passed through a transparent glass prism. These colours can be recombined to give white light again. This is achieved by placing another glass prism upside down behind the first prism. A patch of white light is obtained on a screen placed behind the second prism because the refraction produced by the second prism is equal and opposite to the refraction produced by the first prism.
APPEARS IN
संबंधित प्रश्न
In the following diagram, the path of a ray of light passing through a glass prism is shown:
In this diagram the angle of incidence, the angle of emergence and the angle of deviation respectively are (select the correct option):
(A) X, R and T
(B) Y, Q and T
(C) X, Q and P
(D) Y, Q and P
Study the following diagrams in which the path of a ray of light passing through a glass prism as traced by four students P, Q, R and S is shown:
The student who has traced the path correctly is
(A) P
(B) Q
(C) R
(D) S
State the cause of dispersion of white light passing through a glass prism. How did Newton show that white light of sun contains seven colours using two identical glass prisms. Draw a ray diagram to show the path of light when two identical glass prisms are arranged together in inverted position with respect to each other and a narrow beam of white light is allowed to fall obliquely on one of the focus of the first prism.
A student is observing a diagram showing the path of a ray of light passing through a glass prism. He would find that for all angles of incidence the ray of light bends:
(i) A ray of white light breaks up into its components while passing through a glass prism. Draw a ray diagram to show the path of rays.
(ii) Mark the least deviated colour in your diagram
(iii) Why do different coloured rays deviate differently in a prism?
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.
State the colour seen (i) at X, and (ii) at Y.
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?
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
The splitting of white light into its constituent colours is called .............
What do you understand by the term spectrum?
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 ______.
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 name the wave.
Suggest one way, in each case, by which we can detect the presence of Infrared radiations.
In the diagram, a narrow beam of white light is incident on a right-angled isosceles prism. The critical angle of the material of prism for the yellow colour of white light is 45°. Complete the diagram to show the path of blue, yellow, and red colours of white light till they emerge out of the prism.
Match the Columns:
| Column ‘A’ | Column ‘B’ |
| The wavelength of red light | (a) 600 nm |
| (b) 700 nm | |
| (c) 500 nm |
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?
