Electromagnetic waves are often described as transverse in nature.
(i) Define a transverse wave.
(ii) Using the basic ideas of time–varying electric and magnetic fields, explain qualitatively why the electric field E and the magnetic field B in a plane electromagnetic wave are mutually perpendicular.
(iii) Describe, with justification, the orientation of the vectors E, B and the direction of wave propagation. Draw a labelled sketch to support your answer.
(iv) State how the ratio of the magnitudes E/B is related to the speed of the wave in free space.