Prisms

A ray of light is incident at an angle of incidence, , on one face of a prism of angle (assumed to be small) and emerges normally from the opposite face. If the refractive index of the prism is the angle of incidence , is nearly equal to:

1.		2.
3.		4.

A beam of light consisting of red, green, and blue colours is incident on a right-angled prism. The refractive index of the material of the prism for the red, green, and blue wavelengths is and respectively. 

The prism will:

1.	separate the blue colour part from the red and green colour.
2.	separate all three colours from one another.
3.	not separate the three colours at all.
4.	separate the red colour part from the green and blue colours.

A thin prism having refracting angle is made of glass of a refractive index . This prism is combined with another thin prism of glass with a refractive index . This combination produces dispersion without deviation. The refracting angle of the second prism should be:

1.		2.
3.		4.

The refractive index of the material of a prism is and the angle of the prism is One of the two refracting surfaces of the prism is made a mirror inwards with a silver coating. A beam of monochromatic light entering the prism from the other face will retrace its path (after reflection from the silvered surface) if the angle of incidence on the prism is:

1.		2.
3.		4.	zero

Find the value of the angle of emergence from the prism given below for the incidence ray shown. The refractive index of the glass is .

1.		2.
3.		4.	$\mathrm{}$

A light ray enters through a right-angled prism at point with the angle of incidence as shown in the figure. It travels through the prism parallel to its base and emerges along the face The refractive index of the prism is:

1.		2.
3.		4.