Electromagnetic waves — UPSC CSE 2026 Physics PYQ

The magnetic field H of an electromagnetic wave travels in the -a_z direction in free space with a phase shift constant of 30\text{ rad/m} and an amplitude of \left(\frac{1}{3\pi}\right)\text{ A/m}. If the field has the direction -a_y when t = 0 and z = 0, write the suitable expressions for E and H. Determine the frequency and wavelength of the wave.