Advertisements
Advertisements
प्रश्न
Describe an activity to show that the colours of white light splitted by a glass prism can be recombined to get white light by another identical glass prism. Also, draw a ray diagram to show the recombination of the spectrum of white light.
Advertisements
उत्तर
The phenomenon of dispersion of white light through a prism and then its recombination can be explained with the help of two identical glass prisms. For this to happen, white light is made to made to fall on the surface of the prism. Since different colours of white light have different wavelengths, the amount of bending of light is different. Red light bends the least and violet light bends the most. So, we obtain a spectrum of seven colours, with violet light at the bottom and red at the top. This spectrum is then made to fall on an indentical prism, which is kept inverted. When the spectrum passes through the prism, all the colours bend once again, resulting in their recombination (as shown in the figure below). Hence, the light coming out of the second prism will be white.
APPEARS IN
संबंधित प्रश्न
A ray PQ incident normally on the refracting face BA is refracted in the prism BAC made of material of refractive index 1.5. Complete the path of ray through the prism. From which face will the ray emerge? Justify your answer.
A ray PQ incident on the refracting face BA is refracted in the prism BAC as shown in the figure and emerges from the other refracting face AC as RS such that AQ = AR. If the angle of prism A = 60° and refractive index of material of prism is `sqrt3 `. Calculate angle θ.
What is the cause of dispersion of light
State any two difference between the primary rainbow and secondary rainbow
Give the formula that can be used to determine refractive index of materials of a prism in minimum deviation condition ?
A certain material has refractive indices 1.56, 1.60 and 1.68 rfor red, yellow and violet lightespectively. (a) Calculate the dispersive power. (b) Find the angular dispersion produced by a thin prism of angle 6° made of this material.
A thin prism is made of a material having refractive indices 1.61 and 1.65 for red and violet light. The dispersive power of the material is 0.07. It is found that a beam of yellow light passing through the prism suffers a minimum deviation of 4.0° in favourable conditions. Calculate the angle of the prism.
Three thin prisms are combined as shown in figure. The refractive indices of the crown glass for red, yellow and violet rays are μr, μy and μv respectively and those for the flint glass are μ'r, μ'y and μ'v respectively. Find the ratio A'/A for which (a) there is no net angular dispersion, and (b) there is no net deviation in the yellow ray.
A ray of light is incident on a prism whose refractive index is 1.52 at an angle of 40°. If the angle of emergence is 60°, calculate the angle of the prism.
Calculate dispersive power of a transparent material given : nv = 1.56, nr = 1.54, ny = 1.55.
