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)

(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.
$I=I_0{\exp }^{-ad}$
(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.