Observe the air quality and colour of the sky for a week
(Mention dates). How does the colour of sky changes with the
change in air quality. Explain various reasons based on your
observations which are responsible for the same.
Answers
Answer:
The Appearance of the Sky
The colors we see in the sky come from sunlight that is scattered by molecules in the atmosphere. This process is called Rayleigh scattering. Nitrogen and oxygen make up most of the molecules in our atmosphere, but any gas or aerosol suspended in the air will scatter rays of sunlight into separate wavelengths of light. Consequently, when there are more aerosols in the atmosphere, more sunlight is scattered, resulting in more colorful skies.
Why Is the Sky Blue?
Sunlight is made up of all the colors of light. It appears as white light when all the colors are together. Sunlight travels as waves of energy, and different colors of light have different wavelengths. Red light has long wavelengths, while blue light has short wavelengths. Light bounces off of air molecules in the Earth's atmosphere, scattering in all directions. Blue light is scattered more than other colors of light because of its shorter, smaller waves. Because blue light is scattered more than other colors of light, the sky appears blue.
This is an illustration showing the visible light region of the electromagnetic spectrum, with longer wavelengths to the left and shorter wavelengths to the right.
The visible light region of the electromagnetic spectrum is made up of different sized wavelengths of light. Each wavelength defines a unique color. All wavelengths of visible light together make up white light.
Credit: NASA
A photo of a rainbow in a misty sky over a small mountain town.
A rainbow over Nederland, Colorado.
Credit: UCAR
How Does a Rainbow Form?
Rainbows result from light that scatters inside of water droplets. This is why you only see rainbows after it has rained, when there is water in the atmosphere and the Sun is shining. Sunlight enters a rain droplet and refracts, or bends, as it travels through the droplet. Shorter wavelengths of light bend more than longer wavelengths of light, causing the sunlight to separate into the full spectrum of visible light as it exits the droplet. The resulting rainbow is visible with the longest wavelengths (red) at the top, and the shortest wavelengths (violet) at the bottom.