1. The wavelength of microwaves are longer than that of visible light . Please see the attached image to understand how visible light and microwaves differ in terms of wavelength. You will find that Visible light wavelength is in the range of 400-700 nanometers, or around [tex] 10^{-6} [/tex]m, while microwave's wavelength is around [tex] 10^{-2} [/tex]m.
2. As seen in the above explanation,visible light has a wavelength of around [tex] 10^{-6} [/tex]m while microwaves have a wavelength of around [tex] 10^{-2} [/tex]m. That means microwaves are [tex] 10^{4} [/tex] times the wavelength of visible light. That means they differ in wavelength by 3-4 orders of magnitude