Announcements

• Quiz 5 (this Friday, start promptly at 1:50pm)
  • Construct the expression for plane wave given a description
    • Both complex and real expressions
  • Combine two plane waves and describe the resulting superposed wave

We found a traveling wave solution for the condcutor situation,

$$\widetilde{\mathbf{E}}(\mathbf{r},t) = \widetilde{\mathbf{E}}_0e^{i(\widetilde{k}z-\omega t)}$$

where $\widetilde{k} = \omega^2\mu \varepsilon + i(\omega \mu \sigma)$

True (A) or False (B): This traveling wave is transverse.

(C) I'm not sure.

The magnetic field amplitude in a metal associated with a linearly polarized electric EM wave is:

$$\widetilde{B}_0 = \left(\dfrac{k_R+ik_I}{\omega}\right)\widetilde{E}_0$$

True (A) or False (B): The B field is in phase with the E field.

(C) It depends!

The magnetic field amplitude in a highly conductive metal ($\sigma \gg \varepsilon \omega$) associated with a linearly polarized electric EM wave is

$$\widetilde{B}_0 = \sqrt{\dfrac{\mu \sigma}{\omega}}\dfrac{1+i}{\sqrt{2}}\widetilde{E}_0$$ $$\widetilde{B}_0 = \sqrt{\dfrac{\sigma}{\varepsilon_0 \omega}}\dfrac{1+i}{\sqrt{2}}\dfrac{\widetilde{E}_0}{c}$$

True (A) or False (B): The B field is in phase with the E field.

(C) It depends!