Why is The Sky Blue?

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On a clear sunny day, the sky above us looks bright blue. In the evening, the sunset puts on a brilliant show of reds, pinks and oranges. Why is the sky blue? What makes the sunset red?
To answer these questions, we must learn about light, and the Earth's atmosphere.

 

 

 

THE ATMOSPHERE

The atmosphere is the mixture of gas molecules and other materials surrounding the earth. It is made mostly of the gases nitrogen (78%), and oxygen (21%). Argon gas and water (in the form of vapor, droplets and ice crystals) are the next most common things. There are also small amounts of other gases, plus many small solid particles, like dust, soot and ashes, pollen, and salt from the oceans.
The composition of the atmosphere varies, depending on your location, the weather, and many other things. There may be more water in the air after a rainstorm, or near the ocean. Volcanoes can put large amounts of dust particles high into the atmosphere. Pollution can add different gases or dust and soot.
The atmosphere is densest (thickest) at the bottom, near the Earth. It gradually thins out as you go higher and higher up. There is no sharp break between the atmosphere and space.

Step by Step Guide: Make Windows 7 Faster

                                                                            

 

Windows 7 is a new product of Microsoft but thousand of user complain that their Windows 7 works very slow. People are trying really hard to make Windows 7 faster. Usually people get frustrated working on their slow computer. Windows 7 is the next generation operating system that will mark a dramatic improvement in the way the operating system takes advantage of the graphics.

 

 

Follow these guidelines to improve your Windows 7 working speed:
 1. Disable the Windows 7 Sidebar and Gadgets
If you never use the Gadgets, and if you want to disable the Windows 7 sidebar, here is how you can do it.
Right click on the sidebar and select Properties. On the properties windows untick the check box showing “Start sidebar when Windows Starts”. From now on windows sidebar won’t start when windows 7 start up.