Advertisements
Advertisements
प्रश्न
You are given a disc divided into seven sectors with colours violet, indigo, blue, green, yellow, orange and red in them. What would be its colour when it is rotated rapidly?
Advertisements
उत्तर
Newton’s colour disc— It is a circular disc taken by Newton to demonstrate that the recombination of seven colours produces white light. A circular cardboard disc which is divided into seven sectors and they were painted with the seven colours of VIBGYOR. The disc when rotated at a very high speed appears WHITE.
APPEARS IN
संबंधित प्रश्न
In the following ray diagram the correctly marked angle are:
(a) ∠i and ∠e
(b) ∠A and ∠D
(c) ∠i, ∠e and ∠D
(d) ∠r, ∠A and ∠D
Study the following figure in which a student has marked the angle of incidence (∠i), angle of refraction (∠r), angle of emergence (∠e), angle of prism (∠A) and the angle of deviation (∠D). The correctly marked angles are
(a) ∠A and ∠i
(b) ∠A, ∠i and ∠r
(c) ∠A, ∠i, ∠e and ∠D
(d) ∠A, ∠i, ∠r and ∠D
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.
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.
In the formation of spectrum of white light by a prism:
which colour is deviated least?
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?
The splitting of white light in to seven colors is called ______.
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’.
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?
