An electric charge at rest will produce an electric field around it while a moving charge will produce an electric as well as magnetic field around it. The electromagnetic waves are produced when there is a sudden change in the electric and magnetic field of a moving charge. A stationary charge cannot produce the electromagnetic waves as its electric field stays constant while it is at rest. A charge moving at constant velocity also cannot produce electromagnetic waves as the constant motion means that there is no change in the electric and magnetic field of the moving charge. The electromagnetic waves are produced only when an electric charge undergoes acceleration or deceleration. The change in the electric and the magnetic field of the charge on acceleration or deceleration is manifested in the form of electromagnetic waves.