What's the correct definition of light?1、visible light only2、visible light+infrared+ultraviolet3、radio wave+micro wave+infrared+visible light+ultraviolet+x ray+gamma rayIs light part of the electronmagnetic radiation?or light completely equals to electronmagnetic radiationwhich one is true?
it IS NOT third option. light is a part of the electro magnetic spectrum. It is the same type of wave as infra micro etc but has a different wavelength and frequency. Not that in INFORMAL/everyday speech, infrared and ultraviolet are included as light
When we say light we usually mean the visible, IR and UV portions of the electromagnetic spectrum..
Depends on your source. Look up the definition on the Internet. Browse light definition and find out what the real definition according to a bona fide dictionary, which is the authority on word definitions. Anyway, to my way of thinking, light means visible light. Its the band of EM frequencies processed by our brains and eyes to give us images. Anything other than that is just another EM wave and not visible light. However, commonplace usage lumps UV and IR into the light category. I believe this is a big mistake as we do not process UV and IR into images. Earlier archaic words for light meant visible light as UV and IR were not known back in ancient times. So any definition that includes UV and IR is inconsistent with the origin of the word light.
Usually we define light as the visible spectrum in electromagnetic radiation, which is 400 nanometres to 700 nanometres in wavelength. In other words light is a subset/part of of electromagnetic spectrum (radiation). So, the answer is 1. Light is part of electromagnetic radiation.
