Walker, Halliday & Resnick — Interference: Problem 65

65 Three electromagnetic waves travel through a certain point P along an x axis. They are polarized parallel to a y axis, with the following variations in their amplitudes. Find their resultant at P. \[E_1 = (8.00 \text{ mV/m}) \sin[(2.0 \times 10^{14} \text{ rad/s})t]\] \[E_2 = (5.00 \text{ mV/m}) \sin[(2.0 \times 10^{14} \text{ rad/s})t + 55.0^\circ]\] \[E_3 = (5.00 \text{ mV/m}) \sin[(2.0 \times 10^{14} \text{ rad/s})t - 55.0^\circ]\]