how cell phones work

A cell phone is a great gadget in this modern world. What is a cell phone? A cell phone is actually a radio in certain way. Like a radio, by a cell phone we can communicate to other people in real time. Million people use cell phone for their communication. Even nowadays, people use cell phones to communicate in voice, written and data. Alexander Graham Bell is the person who make great change in the way people communicate to each other. He invented a telephone in 1876. While wireless radio was formally known in 18994 presented by Guglielmo Marconi. By these two technologies, then a cell phone was born. However do you know how actually cell phones work?
This short explanation on how a cell phone work is really wonderful. A cell phone or in long term "cellular telephone' works by transmitting signals of radio to towers of cellular. The towers are networked to a central switching station. The connection usually uses wire, fiber optic-cables, or microwave.
Then the central switching station which handles calls in certain given area is directed connected to the wire-based telephone system. Cellulars are pick up by the towers and relayed to another cellular telephone user or the user of wire-based telephone network.
the towers vary in the capacity and capability to receive signals. Some can receive the signal from short distance and the others can receive more distance. However, there are usually more than one tower in certain given area so that the system can handle the increasing telephone traffic.

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How Rainbow is Formed

Rainbow is one of  optic phenomena that happens in the atmosphere of the earth naturally. We can see it at mountin range, or  when it is cloudy, or  when it is raining and rising of sun. We have to be the other side for looking.  We  just can see it a half of circle form, but acctually the rainbow is a circle form. We can see it perfectly, if it is seen by standing in the high place. It is real that rainbow is a circle form not like parabola form. On the ground, we can not see perfectly, except if we are in the high place like in the air plane or standing on top of  moutain. When we are looking at rainbow’s colors, we will see them that ordered of red is on the highest order,  and purple is on  the lowest order.

Red is more dominant than another color caused by having biggest wave between others. Therefore the red one is in the highest order  and purple one is in lowest order. How rainbow is formed?  Try to watch it when light of sun concerns a 90-degree angle mirror or a glass prism side, or surface of  soap foam. We can see colors on the light. The light is rayyed to be some  wave lenght of light that it is seen by our eyes as red, bright red, yellow, green, blue and purple. These colors are compnents of light that they are called visible light. The other component is invisible light such as infrared (red is in the right side), and ultraviolet (bright red is in the left side).

So, we can see the beautiful rainbow because there are some processes to be beautiful rainbow that it appears in the sky.

 

How does Rain Happen?

Rain is the primary source of fresh water for most areas of the world, providing suitable conditions for diverse ecosystems, as well as water for hydroelectric power plants and crop irrigation.

The phenomenon of rain is actually a water circle. The concept of the water cycle involves the sun heating the Earth's surface water and causing the surface water to evaporate. The water vapor rises into the Earth's atmosphere. The water in the atmosphere cools and condenses into liquid droplets. The droplets grow until they are heavy and fall to the earth as precipitation which can be in the form of rain or snow.

However, not all rain reaches the surface. Some evaporates while falling through dry air. This is called virga, a phenomenon which is often seen in hot, dry desert regions.