Question 349: Waves Optics

Question

A beam of unpolarized light passes through a tourmaline crystal A and then it passes through a second tourmaline crystal B oriented so that its principal plane is parallel to that of A. The intensity of emergent light is $$I_0$$. Now B is rotated by $$45^{\circ}$$ about the ray. The emergent light will have intensity $$\left(\cos 45^{\circ}=\frac{1}{\sqrt{2}}\right)$$

Accepted Answer

Using law of Malus,
$$\begin{aligned}
\mathrm{I} & =\mathrm{I}_0 \cos ^2 	heta \
& =\mathrm{I}_0\left(\cos ^2 45ight) \
& =\mathrm{I}_0\left(\frac{1}{\sqrt{2}}ight)^2 \
& =\frac{\mathrm{I}_0}{2}
\end{aligned}$$

Answer

$$\frac{\mathrm{I}_0}{2}$$

Answer

$$\frac{\mathrm{I}_0}{\sqrt{2}}$$

Answer

$$\frac{\sqrt{2}}{\mathrm{I}_0}$$

Answer

$$\frac{2}{\mathrm{I}_0}$$

Waves Optics

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