Question
Is it necessary that an optically denser medium should possess greater mass density than an optically rarer medium?
Solution
It is not necessary that an optically denser medium may possess greater mass density than an optically rarer medium.
For example, kerosene or turpentine oil, having higher refractive index, is optically denser than water, although its mass density is less (as oil floats on the surface of water) than that of water.
For example, kerosene or turpentine oil, having higher refractive index, is optically denser than water, although its mass density is less (as oil floats on the surface of water) than that of water.
