Question

Find out, from Table, the medium having highest optical density. Also find the medium with lowest optical density.

Material medium	Refractive index	Material medium	Refractive index
Air	1.0003	Canada Balsam	1.53
Ice	1.31	–	–
Water	1.33	Rock salt	1.54
Alcohol	1.36	–	–
Kerosene	1.44	Carbon disulphide	1.63
Fused quartz	1.46	Dense flint glass	1.65
Turpentine oil	1.47	Ruby	1.71
Benzene	1.50	Sapphire	1.77
Crown glass	1.52	Diamond	.42

Answer 1

1. The medium with maximum optical density is diamond whose refractive index is 2.42.
2. The medium with minimum optical density is air whose refractive index is 1.0003.
3. The optical density of a medium is directly related to the refractive index of that medium. A medium with the highest refractive index will have the highest optical density and vice versa.
4. It can be observed from the table that diamond and air, respectively, have the highest and lowest refractive index. Therefore, diamond has the highest optical density and air has the lowest optical density.