Dispersion and Spectra Physics - Dispersion and Spectra

The angular dispersion produced by a prism:

1. Increases if the average refractive index increases.
2. Increases if the average refractive index decreases.
3. Remains constant whether the average refractive index increases or decreases.
4. Has no relation with average refractive index.

Which of the following quantities increase when wavelength is increased? Consider only the magnitudes.

1. The power of a converging lens.
2. The focal length of a converging lens.
3. The power of a diverging lens.
4. The focal length of a diverging lens.

Which of the following quantities related to a lens depend on the wavelength or wavelengths of the incident light?

1. Power.
2. Focal length.
3. Chromatic aberration.
4. Radii of curvature.

By properly combining two prisms made of different materials, it is possible to:

1. Have dispersion without average deviation.
2. Have deviation without dispersion.
3. Have both dispersion and average deviation.
4. Have neither dispersion nor average deviation.

If a glass prism is dipped in water, its dispersive power:

1. Increases.
2. Decreases.
3. Does not change.
4. May increase or decrease depending on whether the angle of the prism is less than or greater than 60°.

The refractive index of a material changes by 0.014 as the colour of the light changes from red to violet. A rectangular slab of height 2.00cm made of this material is placed on a newspaper. When viewed normally in yellow light, the letters appear 1.32cm below the top surface of the slab. Calculate the dispersive power of the material.

Suggest a method to produce a rainbow in your house.

"Monochromatic light should be used to produce pure spectrum". Comment on this statement.

The focal lengths of a convex lens for red, yellow and violet rays are 100cm, 98cm and 96cm respectively. Find the dispersive power of the material of the lens.

Two prisms of identical geometrical shape are combined with their refracting angles oppositely directed. The materials of the prisms have refractive indices 1.52 and 1.62 for violet light. A violet ray is deviated by 1.0° when passes symmetrically through this combination. What is the angle of the prisms?

A certain material has refractive indices 1.56, 1.60 and 1.68 for red, yellow and violet light respectively.

1. Calculate the dispersive power.
2. Find the angular dispersion produced by a thin prism of angle 6° made of this material.

A flint glass prism and a crown glass prism are to be combined in such a way that the deviation of the mean ray is zero. The refractive index of flint and crown glasses for the mean ray are 1.620 and 1.518 respectively. If the refracting angle of the flint prism is 6.0°, what would be the refracting angle of the crown prism?