Define emissive power, coefficient of emission and absorptive power.

Define emissive power of a body. State its unit and dimension.

ir the refractive indices of crown glass for red yellow and violet colours are 1.5140, 1.570 and 1.5318 respectivelyand ofr flint glass these values are 1.6434, 1.6852 respectively , then the dispersive powers for crown and flint glass are respectively

Define absorptive power, state its unit and dimension.

The refractive index of the prism for violet colour is 1.7 and that for red is 1.65. Then dispersive power of the material of prism is

The refractive index of the prism for violet colour is 1.7 and that for red is 1.65. Then dispersive power of the material of prism is

In the visible region the dispersive powers and the mean angular deviations for crown and flint glass prisms are omega, omega' and d, d' respectively. The condition for getting deviation without dispersion when the two prisms are combined is

Define dispersion of light.

The dispersive power ( omega ) of the material of prism is given by

The dispersive power (omega) of the material of prism is given by