Question

A beam of polarized light with an average intensity of 14.5 W/m² is sent through a polarizer. The transmission axis makes an angle of 25.0° with respect to the direction of polarization. Determine the rms value of the magnetic field of the transmitted beam.

Answer 1

Answer:

Explanation:

Intensity, Io = 14.5 W/m²

θ = 25°

By the law of Malus

$I = I_{o}Cos^{2}\theta$

$I = 14.5Cos^{2}25$

I = 11.91 W/m²

Now the formula for the rms value of magnetic field is given by

$I = \frac{cB_{rms}^{2}}{\mu _{0}}$

$B_{rms}^{2}=\frac{11.91\times 4\times 31.4\times 10^{-7}}{3\times 10^{8}}$

Brms = 2.23 x 10^-7 tesla