What colour is an orange in the dark

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This question may have been asked here but I didnt see it.

This is a classic question from the ABC science forum in australia and the question also made its way to england infected the BBC science forum

ha ha ha ....................attempt to answer it at your own peril :)
Hi, mick ...

Welcome to Sciforums.

Question: Is it a transgenetic orange?

If so, a pale green glow.
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well theres a few points to this:

how dark is it? If it's night time and you can only just make out a silhouette, then the orange has no colour, because for it to have colour it would have to be subjected to light, (white light or a light that carries a colour that the orange reflects)

Since Orange is a mixture of Red and Yellow, the light sources it could reflect are White light (which in the dark wouldn't be existant), or it could be Infra-Red which is present at night from the fluctuation of free floating atoms and molecules.

Of course infra-red is just before the eyes visual spectrum, otherwise we would be able to see at night.

Green would be within our visual spectrum of light and wouldn't occur at night (of course I'm going ont he assumption that it's pitch black)

The questions you could then ask are:
Is the orange moving? If so is it moving away or towards you?

I mention this because in normal light if something is travelling towards you, it has a higher frequency of light stemming up to ultraviolet, while if it's travelling away it will be more towards the infra-red end of the scale.

Of course you wouldn't be able to notice this unless you used particular types of equipment like a Spectrophotonmeter.

This would mean also that if the orange was travelling towards you (or you towards it) it might have a perception of green.
Of course I can't apply the speed you need to be approaching the orange, or the orange approaching you.
Wrong answer

The answer given is not for the question asked. It is the classic question of "If a tree falls in the forest and nobody is around to hear it, does it does it make a sound?" Its a deeper kind of question then that. ME THINKS:p

By the way.. has anyone ever read, The Hichhikers Gude to The Galaxy.....:D

Makes you think on some of the same type of questions....
What colour is an orange in the dark?


Well if the orange is ripe, then it will be orange..

if it isn't ripe, then it will be green..

well that is my experience of oranges anyway :)

The answer is correct, it's just the question isn't right.
A classic "42" conundrum.
colour of an orange in the dark.

I believe it would be helpful to understand why an orange is orange when illuminated. Light waves enter our eyes and set off a reaction in the optic nerve that is associated with the external phenonoma of frequencies that are consistant with the physical properties of the orange. That is to say that the inherent properties of an orange are a constant, and that an organisms ability to recognize said properties using the interpretation of external stimuli such as light is variable. Raising the question of the colour of an orange in the dark is almost like raising the question of whether or not an orange CAN exist in the dark.
<<...What colour is an orange in the dark...>>

Since color is a subjective visual quantization of available light (Orange is a specific range of colors falling within the visually perceptible portion of the spectrum of electro-magnetic wavelengths), and vision requires the eye to receive and absorb visible wavelength photons in sufficient quantity to induce chemical activity, in the dark Orange will have no color at all.

Colour is a horse of a different color.

I smiled when I saw this, it also reminded me of the tree in the forest. The answer is slightly darker than its surrounding darkness, I think!!:confused: :rolleyes: :rolleyes:
Color is a property of the orange, yes ?
Then it's still orange in the dark. We just can't perceive it.

The chemical composition of the outer margins of the orange reflects light predominantly of wavelengths that we perceive as 'orange'.
The chemical composition is still there in the dark, only very few photons reflect off it.
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You can't have colour in the absence of light. The orange will only have colour when exposed to light- basic physics.
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