Question
Hey,
I only need help with part 3 of the question.
Thanks!!!
The figure shows three polarizers that have transmission axes indicated by the solid lines. The angle of rotation for each polarizer relative to the vertical polarization of the light incident on the first polarizer is also indicated (the polarization of light leaving the laser is in the vertical direction). If the intensity of light incident on the first polarizer is 6.2 W/m2, what is the intensity of light leaving the first polarizer, measured at A? (Assume that any decrease in intensity with distance can be ignored.) What is the intensity of light leaving the third polarizer, measured at C? (Assume the distance between the polarizers is small enough that any decrease in intensity with distance can be ignored.) If the vertical polarization of the light incident on the first polarizer is in the z-direction and the wave is propagating in the z-direction, determine the electric and magnetic field amplitude vectors, and give them in unit vector notation. (Hint. They will both have x- and y-components.)
Explanation / Answer
Intenity I = E^2/2uoC
E^2 =6.2*4Pi*10-7*2*3*10^8
E=68.35 N/C
b. magnetic field B= E/c = 68.35/3*10^8 =2.278*10^-9 T
in vector form E = 69.35 N/C
B= 2.278*10^-9 J T