Q.State qualitatively what carries the energy in an electromagnetic wave as it travels through space, and name the physical quantity that describes the rate at which this energy is transported per unit area.

What carries the energy. An electromagnetic wave is made up of an oscillating electric field $\vec{E}$ and an oscillating magnetic field $\vec{B}$, and each of these fields, exactly as for a charged capacitor's electric field or a current-carrying inductor's magnetic field (both met in earlier chapters), stores real energy in the region of space it occupies. As the wave moves outward, this stored field energy moves along with it, being continuously transported from the source (an oscillating charge, Section 8.3) to wherever the wave is eventually absorbed. …

Identify the fields themselves as the carriers of energy, then name and briefly describe i …

• Saying the wave 'has no energy' because it involves no moving matter -- field energy is real, physical energy, exactly like the energy stored in a charged capacitor. …