Which

electromagnetic

waves have the

largest wavelength?

The electromagnetic waves with the longest wavelengths are the ones we call "radio waves".

They're anything with a wavelength of 1 millimeter or more. (Frequency of 300 GHz or less.)

That's longer than gamma rays, X-rays, ultraviolet, visible light, and infrared radiation.

Answer:Red has the longest wavelength and violet has the shortest wavelength. When all the waves are seen together, they make white light. Ultraviolet (UV) light-is radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400.