Two electromagnetic waves are represented by the following expressions: E = Ae(k=-wt) E Ē2 = Ae"(kz-wt+a)E, where both A and a are real. (a) For each wave, determine its polarization state. Calculate the time-average Poyning (5). vector Consider the superposition of the two waves E3 = E1 + E2. (b) Calculate the time-average Poyning vector (5.). (c) For what value(s) of a will E, be a circularly polarized wave?

The helium-neon laser usually used in classrooms typically provides an intensity of about 14 What are the rms electric and magnetic fields 1m/wm for such a beam? Hint: Poynting vector We know that electric and magnetic fields store energy, and so as EM wave propagates, it carries energy. The rate of energy flow, in watts per square meter, can be shown to be: S = ¹ EX B Ho S is the Poynting vector. It points in the direction the energy is propagating. In a plane wave, EL B,and E=cB, so |S= Wmm². = EB= 1 CHO -E²=__B² но Но 1 = 1/² &₁₂ E²³C с Is /IM√x (mm) 2

A nonsinusoidal electromagnetic wave has uniform electric and magnetic fields. The magnitude ofthe Poynting vector for this wave is 11.0 W>m2. Find (a) the magnitudesof the electric and magnetic fields and (b) the energy density in the wave.

A solar sail 32.5 m2 in area and made of an absorptive material is orbiting the Sun in space. The Sun light normally incident on the solar sail exerts a radiation pressure of 3.22E-6 N/m2 on it. If the material is replaced with a reflective material that can complete reflect the Sun light, what will the radiation pressure become (in N/m2)?