why cannot we see air?

Question

i think the answer is that it does not reflect it but why is it so?though its molecules are loosely packed but are not absent.why are not we able to see it as somewhat light should be reflected.

Answer 1

You are correct, some light is reflected. But stop and think about this for a minute:
What is the intensity of the light reflected from these particles of air as compared to the background light?
Think of it this way, could you see a light bulb that was placed between you and the sun, say at a distance of 100 yards? No, because though the light bulb IS sending light to your eyes, the background light overwhelms it. Your eyes aren't sensitive enough to pick out such a tiny source in the massive background. Hope that helps, and you were on to something, you just haven't studied signal noise yet!!

Answer 2

A very simple answer is the air molecules are not scattering enough intensity of light which can be sensed by our eye. Further, because of the fact the speed of light in air and vacuum is nearly the same; one can infer that the air does not practically absorb the light energy. Hence, all light is transmitted through them.

A little bit more elaborate answer is due to the properties of dispersion and absorption of light rays.

When a light ray (in general all electro magnetic radiation) is propagated through matter, the electric charges of the molecules are set into vibratory state. There is a relative displacement of the center of gravity of all electrons to the center of gravity of the almost stable center of gravity of the atomic nuclei’s positive charges.

The dipole moment of a molecule is inversely proportional to the difference in the square of the natural frequency of the electron energy level and the square of the frequency of the incident light.

Every molecule has many natural frequencies, as there are different energy levels.

If the incident light’s frequency is near the natural frequency the dispersion is called anomalous dispersion and the behavior of absorption and dispersion is complex.

But outside this region generally, higher the frequency, higher is the absorption.

In the case of air molecules, they are free to move and the natural frequency (which depends upon the rigidity of the bond) is zero.

Therefore, the energy is not absorbed and the light ray passes through them as in the case of vacuum.

The above is only a general description and in the case of light rays the refractive index of the medium ranges from zero to unity and to a value very much greater than unity. Hence their behavior is much more complicated in a medium other than air.

A crude way of description is when light passes through air, air molecules move away allowing the light to pass through them.

Answer 3

A product of evolution. Air is "invisible" in visible light but is excessively foggy in other wavelengths. Those animals that could only see wavelengths that make air visible would be at a distinct disadvantage and would have a higher chance of getting eaten or killed by those that could see them using wavelengths where air is invisible. It's kind of like this: Imagine you out in the middle of the savannah in Africa at midnight with no moon out. You have a baseball bat and there's a lion not too far away. Who has the advantage?

Answer 4

Air is made of a number of gases. Gases are made up of atoms and molecules that dispersely seperated and at free random positions, at larger distance than liquid or solid atoms or mocules. And these tkiny paricles do not reflect light.

Answer 5

Go outside at night, in a dark area and look at the sky, you will see twinkling stars. This is due to atmospheric refraction, among a host of other variables. The Northern Lights, are a good example of seeing air via atmospheric refraction. So to answer your question, you can see air, it just depends on where you look for it. Bubbles in a Fish Tank=Air.

Answer 6

substances in the air like oxygen nitrogen etc. are colorless by nature and they dont reflect light as mentioned. while this is true, some gases are visible under certain conditions. For example the fluorescent bulb is certainly visible.

Answer 7

Air has the property of not reflecting any visible light, thus it appears colorless to us.

Answer 8

everything emits radiation on some wavelength. things maintains their equilibrium that way, their rest state, as it were. we are not all seeing, all knowing creatures! why would you be suprised by such limitations? it would be like eye photoreceptor cells that could capture background radiation... in space we have yet to 'see' dark matter. not knowing the limitations of dark matter, especially its subatomic limitations, it may be all around us, like air.

Answer 9

If you go to L.A. you can see air. It's a little yellow/orange/brown sometimes.

Answer 10

It's much much much less dense then solid objects we easily see.