(a) When the oscillating electric and magnetic fields are along the X and Y-direction, respectively
(i) point out the direction of propagation of electromagnetic wave,
(ii) express the velocity of propagation in terms of the amplitudes of the oscillating electric and magnetic fields.
(b) How do you show that an em wave carries energy and momentum ?

Explanation

(i) Z-axis. (ii) v = E/B (iii) An electromagnetic wave exerts a force on the surface on which it falls. The force exerted by the wave per unit area of the surface is known as radiation pressure. The wave also delivers energy and momentum to the surface. Because these waves are having perpendicular electric and magnetic fields. The electric and magnetic fields are associated with energy density. Hence, we can say that an electromagnetic wave carries energy and momentum.