Q.State, in qualitative terms, how Maxwell's equations predict the existence of electromagnetic waves that can travel through empty space without needing any material medium.

The two feeding relationships. Maxwell's equations, taken together, contain two relationships that make an electromagnetic wave possible: (1) the Ampère-Maxwell law (Section 8.2) says a CHANGING electric field produces a magnetic field, exactly as a conduction current would; (2) Faraday's law (met in the Electromagnetic Induction chapter) says a CHANGING magnetic field produces an electric field.

Why this predicts a self-propagating wave. Suppose, at some point in space, the electric field starts changing (Section 8.3 -- because of an accelerating charge nearby). By relationship (1), this produces a changing magnetic field at a neighbouring point. That changing magnetic field, by relationship (2), produces a changing electric field at a point further along still. This changing electric field then produces a changing magnetic field further along again, and so on indefinitely -- each field regenerating the other and the whole disturbance moving steadily outward through space, entirely under its own power, needing no further push from the original charge once it has been set going. …

State the two field-regeneration relationships from Maxwell's equations and show how, chained together, they pr …

• Only mentioning ONE of the two regenerating relationships (e.g. only Faraday's law) instead of both, which together are what make the process self-sustaining. …