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Question
Hello sir

Sir my question  which i had mentioned down may be very irritative and senseless according to me. Sir you only tell was it really


Sir my question is  why only  light makes things visible what is in the light why only ight we have our eyes but why light makes us visible. except light there is no other thing on the earth which makes things visible.

Answer
Well that's what the word means, so I think you mean "perceptible."  We define the visible spectrum of light by what our eyes are capable of receiving and reacting to.  If we were bats, we might define an area of the spectrum of sound that would allow us to perceive objects through echolocation.  So, in a very true sense, light is not the only thing which can interact with an object and allow it to be perceived.  Also, I have a camera that attaches to my phone which takes pictures in the infrared.  Between that and things like radio telescopes, there are at least many forms of light which can be converted into images which we can see.  To allow us to perceive something in the way you're using the word "visible," you need something which can interact with it and which our sensory organs are capable of receiving and interpreting.  Light, sounds, and smells fit this description, which is why we define visible as that which interacts with light between about 400-700 nm in wavelength.  Why is there not some other thing which behaves like light?  Well, that's the way the universe is and we really don't have a way to change that.

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Dr. Stephen O. Nelson

Expertise

I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

Experience

I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Education/Credentials
Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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