Why Air Is Invisible: Why is air not visible? Know why air has no color, how it is felt, why there is no air in space and the scientific reason behind it.
Why Air Has No Color: We breathe air every moment. Without air, humans can survive for only a few minutes. When strong wind blows, trees start shaking, kites start flying and coolness is felt. But do you know why such an important thing is not visible? The answer to this is hidden in science. Air is present everywhere, but its structure and properties are such that our eyes cannot see it directly.
What is air after all?
Air is not a single gas, but a mixture of many gases. This mainly includes-
- Nitrogen
- Oxygen
- Argon
- Carbon Dioxide
- Water Vapor
- Some other gases are present in very small quantities.
- The molecules of these gases are very small and keep moving around continuously.
Why is air not visible?
To see anything, it is necessary that it reflect or scatter light. Air molecules are so small and so far apart that they do not transmit enough light back to our eyes under normal conditions. Therefore the air appears transparent. That is, air is present, but because of it such light does not reach our eyes so that it can be seen separately.
Then how do we feel the wind?
Even though wind is not visible, its effect can be easily felt. As –
- When strong wind blows, tree branches start shaking.
- One feels cool when the fan runs.
- Kite flies with the help of wind.
- The flag starts waving.
- That is, we do not see and feel the wind, but the impact of the wind.
Sometimes air is visible, why does it feel like this?
Actually, we do not see air, but other things present in the air. As-
- dust
- smoke
- Fog
- Cloud
- Steam
When the wind blows these particles with it, it appears as if the wind is visible. Whereas in reality it appears to be small droplets of dust or water. For example, in the sunlight, flying dust is clearly visible in the light coming from the window. There we do not see air, but dust particles floating in the air.
Read this also- Why Leaves Are Green: Why are leaves green?
Does air have any color?
Air has no color in normal conditions. For this reason it appears transparent. However, if there is a lot of dust, smoke or pollution in the air, it may appear cloudy or light brown. This is not the color of the air, but the impact of the particles present in it.
Is there air in space too?
No. Earth’s atmosphere contains air, but space is almost a vacuum. Vacuum is a place where there is no gas or air. There is no oxygen and air required for breathing. For this reason, astronauts have to wear space suits, which have a provision for oxygen.
Read this also- Why do trees provide oxygen?
Important data related to air
- Earth’s atmosphere consists of about 78% nitrogen, 21% oxygen, and about 1% other gases.
- On an average, a human being breathes 20,000 to 25,000 times a day.
- Atmospheric pressure at sea level is approximately 101.3 kilopascals (kPa) or 1 atmosphere (1 atm).
- The size of air molecules is about nanometers, so they cannot be seen with normal eyes.
- The Earth’s atmosphere is thought to extend to about 10,000 km, although most of its mass is within the first 15–20 km.
Content Source: NASA, National Oceanic and Atmospheric Administration (NOAA), Encyclopaedia Britannica, US Environmental Protection Agency (EPA), Khan Academy.