試題詳解

7. Which are correct with the Poynting vector ?
(A) is the energy per unit area and per unit time, transported by the electromagnetic fields.
(B) is the electromagnetic force per unit area acting on a surface.
(C) /c² is the momentum current density transported by the fields.
(D) /c² is the momentum per unit volume stored in the electromagnetic fields.
(E) /c² is the work done on the charges by the electromagnetic force.