Question

Refractive index of material is equal to tangent of polarizing angle. It is called:

• A. Brewster's law
• B. Lambert's law
• C. Malus law
• D. Bragg's law

Answer 1

Answer: (A)

Brewster's law

Answer 2

(a) Brewster's law states that when ordinary light is incident on a transparent surface at polarizing angle $({{i}_{p}})$ for that surface, the tangent of angle of polarisation is equal to the refractive index $(\mu )$ of the medium of surface, that is, $\mu =\tan {{i}_{p}}$ (b) Lambert's law concerns to rate of absorption of radiation as it travels deeper into a medium. It states that the intensity $I$ of radiation falls off exponentially with distance d in the medium. $I={{I}_{0}}{{\exp }^{-\alpha d}}$ (a) Brewster's law states that when ordinary light is incident on a transparent surface at polarising angle $\left(i_{p}\right)$ for that surface, the tangent of angle of polarisation is equal to the refractive index $(\mu)$ of the medium of surface, that is, (b) Lambert's law concerns to rate of absorption of radiation as it travels deeper into a medium. It states that the intensity $I$ of radiation fails off exponentially with distance $d$ in the medium. $I=I_{0} \exp ^{-a d}$ (c) Law of Malus states that intensity of light coming out of analyser is proportional to the square of the cosine of the angle between the plane of analyser and polariser. $I=I_{0}\cos ^{2}\theta$ (d) According to Bragg's law if a beam of $X$-rays of wavelength $\lambda$ is directed at a crystal with parallel crystal planes that are distance d apart, then the reflected $X$-rays from each plane undergo interference.