EM Waves Problem 4:   Radio waves travel through air at approximately the speed of light, c. Imagine your local FM radio station broadcasts plane waves travelling in the negative x-direction with a frequency of f = 104.5 MHz. The waveform of the electric-field component is E(x, t) = E0sin(Φ(x, t)), where Φ(0, 0) = 0 and the amplitude is E0 = 0.46 N/C.  Part (a)  Enter an expression for the function Φ(x, t) in radians, in terms of the defined quantities, the position, x, and the time, t.   Part (b)  Calculate the value of the electric field, in newtons per coulomb, of the wave at the position x = -3.8 m at the time t = 0.015 μs.

Unpolarized light with an initial intensity of 32 W/m2 is incident on a perfect polarizing material that allows light through with a vertical orientation. The light then passes through a second polarizer that is rotated 450 with respect to the first. Finally, the light passes through a third polarizer that is oriented at 900 with respect to the first. What is the intensity of light that makes it through the first polarizer? A. 0 What is the intensity of light that makes it through the second polarizer? B. 2 W/m2 |What is the intensity of light that makes it through all three polarizers? C. 4 W/m2 D. 8 W/m2 E. 16 W/m2 F. 32 W/m2

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A 6.0 mW vertically polarized laser beam passes through a polarizing filter whose axis is 75° from vertical. What is the laser-beam power after passing through the filter?A. 0.40 mW        B. 1.0 mWC. 1.6 mW          D. 5.6 mW