The ocean looks blue because red, orange and yellow (long wavelength light) are absorbed more strongly by water than is blue (short wavelength light). So when white light from the sun enters the ocean, it is mostly the blue that gets returned. Same reason the sky is blue.
In other words, the color of the ocean and the color of the sky are related but occur independently of each other: in both cases, the preferential absorption of long-wavelength (reddish) light gives rise to the blue. Note that this effect only works if the water is very pure; if the water is full of mud, algae or other impurities, the light scattered off these impurities will overwhelm the water's natural blueness.
www.facebook.com/atcdq
Acid rain is rain consisting of water droplets that are unusually acidic because of atmospheric pollution - most notably the excessive amounts of sulfur and nitrogen released by cars and industrial processes.
Acidity itself is determined based on the pH level of the water droplets. PH is the scale measuring the amount of acid in the water and liquid. The pH scale ranges from 0 to 14 with lower pH being more acidic while a high pH is alkaline; seven is neutral. Normal rain water is slightly acidic and has a pH range of 5.3-6.0. If pH of rain is less than 5.3, then it's acid rain..\
What are the causes?
Acid deposition can occur via natural sources like volcanoes but it is mainly caused by the release of sulfur dioxide and nitrogen oxide during fossil fuel combustion. When these gases are discharged into the atmosphere they react with the water, oxygen, and other gases already present there to form sulfuric acid, ammonium nitrate, and nitric acid. These acids then disperse over large areas because of wind patterns and fall back to the ground as acid rain or other forms of precipitation.
What are its effects?
There are many problems and effects caused by acid rain. Acid rain can cause buildings, statues and bridges to deteriorate faster than usual. Another problem is it harms thousands of lakes, rivers, and streams worldwide. It disrupts lake ecosystems and kill wildlife in affected lakes, rivers and streams. Acid rain also damages soil and the tree roots in it. When soil is acidified, tree roots are damaged, leaving them not able to draw in enough nutrients to support the tree. When acid rain falls on trees, it makes their leaves turn brownish-yellow and the tree can no longer carry out photosynthesis properly. Another problem is it will harm people when they breathe in smog, acid rain in one of its many forms.
What can be done ?
Acid rain can be prevented by reducing emissions that come from the mining industries, burning of fuels for electrical power generation, oil operations, and reducing fuel emissions from cars and trucks. Reduce our use of products that produce chlorofluorocarbons that are released into the atmosphere by actively conserving the use of your air conditioning. Become energy wise by conserving energy through the use of fluorescent lights, closing off rooms you do not use, and use washers, dryers, and dishwashers only when full. Last but not lease please recycle packaging and other disposable products.
Source: about.com, ask.com
www.facebook.com/atcdq
Unlike the Earth, the Moon does not have an atmosphere. Temperatures on the Moon’s surface fluctuate dramatically from blistering heat during the day (100° C) to frigid cold during the night (-173° C). With no atmosphere, there is also no wind. Footprints of the Apollo astronauts and those of future explorers may last for thousands of years!
Image credit and source: NASA
www.facebook.com/atcdq
An ATM (Automated Teller Machine) is a computerized system individuals can use to deposit money into their banking accounts, withdraw money from their accounts, check balances and transfer money from one account to the other. ATMs can either be part of a specific bank (a Suntrust ATM, for example), or an independent entity that has contracts with several banks and credit card companies (a Presto machine, for instance). The former are usually found in stand alone booths or on the outsides of a bank, while the latter are usually found in other public places, such as grocery stores and malls.
Working:
In order to access various accounts, ATM computers are connected to complex interbank networks, which allows customers from many different banks to access their accounts through the machine. There are several of these interbank networks; among them are Cirrus and LINK. In order to provide access to the customer, ATMs rely on authorization from the financial institutions. To cover the costs of operation and the fees that involve belonging and accessing the networks, most independent ATMs charge a fee for each transaction. These fees usually range from 30 to 50 rupees.
The ATM is made up of much more than a computer, however. In order to perform all of its functions, the ATM has many different parts. These include the computer, which includes the interface and the keypad for the customer to use, and a magnetic card reader. The latter allows the machine to read the magnetic strip on the back of a customer's debit or ATM card. The machine will also include a display screen, function buttons (usually placed near the screen and covering the functions of saying "yes," "no," and "cancel"), a printer and a cash drawer. Depending on the ATM, it may also provide envelopes for deposits and security camera...
source: ehow.com
www.facebook.com/atcdq
Normally if you cool a liquid it becomes dense. Same thing happens to water till 4 degrees Celsius. Further cooling below 4 degree Celsius causes water to expand. Water freezes to form ice at 0 degree Celsius, and expands further.
Due to low density of ice compared to the density of water, the ice floats on water.
Due to this nature of water, i.e. it is densest at 4 degrees, the 4 degree water goes to the bottom of lakes. Only the surface gets too cold and freezes. Ice is also a bad conductor of heat, this slows down the freezing of lower layers. This way marine life in water, can remain in water, although the surface freezes to form ice...
Source: answers.com
www.facebook.com/atcdq
In spite of popular misconception, you don't yawn because you're tired.
You yawn because your body has built up too much carbon dioxide and needs to release it.
When you're in an inactive state (sitting in class or something like that) your body does not have much opportunity to expel excess carbon dioxide. Excess carbon dioxide in the bloodstream is dangerous, so your body responds by yawning and expelling more carbon dioxide that you would normally do by breathing.
When exercising, you breathe heavily, so it's easy to expel excess carbon dioxide. It only becomes an issue when you're resting... whether it's because you're tired or because you're bored and sitting still.
Yawning does seem to be contagious, but that seems to be a psychosomatic effect. Basically, you see someone yawn, and you feel compelled to yawn. I don't know that there's much more to that. Some things in biology are just quirky that way, or we just don't understand them well enough yet.
Source: answers.yahoo.com
www.facebook.com/atcdq
Everyone who has been to the beach knows that seawater is salty. Everyone also knows that fresh water in rain, rivers, and even ice is not salty. Why are some of Earth’s waters salty and others not? There are two clues that give us the answer. First, “fresh” water is not entirely free of dissolved salt. Even rainwater has traces of substances dissolved in it that were picked up during passage through the atmosphere. Much of this material that “washes out” of the atmosphere today is pollution, but there are also natural substances present.
The Great Salt Lake, Dead Sea, and other salt lakes have no outlets. All the water that flows into these lakes escapes only by evaporation. When water evaporates, the dissolved salts are left behind. So a few lakes are salty because rivers carried salts to the lakes, the water in the lakes evaporated and the salts were left behind. After years and years of river inflow and evaporation, the salt content of the lake water built up to the present levels. The same process made the seas salty.
"Wherever water comes into contact with the rocks of Earth’s crust, either on land or in the ocean or within the oceanic crust, some of the minerals in the rock dissolve and are carried by the water to the ocean. The salt content of seawater does not change because new minerals are forming on the sea floor at the same rate as salt is added. Thus, the salt content of the sea is at steady state."
www.facebook.com/atcdq
When warm wet air rises, it cools and water vapour condenses to form clouds. A cloud is made of small drops of water or ice crystals, depending on its height and how cold its surrounding air is. To form rain, water vapour needs what's called a condensation nucleus, which can be tiny particles of dust, or pollen, swept up high into the atmosphere. When the condensing droplets that form the cloud get large and heavy enough to overcome the upward pressure of convection, they begin to fall.
Rain is restricted to drops of water that fall from a cloud. They have a typically diameter of at least 0.5 mm. No matter what the intensity of rain is the size of the drop rarely exceeds about 5 mm. Larger drops do not survive as the process of surface tension which holds the drop together is exceeded by the frictional drag of air and therefore larger drops break apart into smaller ones.
www.facebook.com/atcdq
Chemistry:Dirt that is not easily brushed off or removed with water alone actually has some form of fat or grease in it. Since oil and water repel each other, water alone can't surround and remove oil.Soap has hydrophilic(water loving) molecules that are attracted to water on one end and lipophilic(oil loving) molecules attracted to oil on the other end.
Function:
The soap molecule surrounds the grease and the lipophilic ends attaches to the fats and oils. The hydrophilic ends are attracted to water, this allows the soap to trap the dirt and wash it down the drain with the water.
Types:
Different soaps are made for different purposes. Beauty and bath soaps have ingredients in them that are gentle on the skin. Laundry detergent is made specifically to clean clothes. Some soaps are made to have low suds, such as those used in high-efficiency or HE washing machines.
http://www.facebook.com/atcdq
WHY IS THE SKY BLUE?
It is easy to see that the sky is blue. Have you ever wondered why? A lot of other smart people have, too. And it took a long time to figure it out!
The light from the Sun looks white. But it is really made up of allthe colors of the rainbow. Light energy travels in waves, too. Some light travels in short, "choppy" waves. Other light travels in long, lazy waves. Blue light waves are shorter than red light waves.
All light travels in a straight line unless something gets in the way to—
reflect it (like a mirror)
bend it (like a prism)
or scatter it (like molecules of the gases in the atmosphere)
Sunlight reaches Earth's atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.
Closer to the horizon, the sky fades to a lighter blue or white. The sunlight reaching us from low in the sky has passed through even more air than the sunlight reaching us from overhead. As the sunlight has passed through all this air, the air molecules have scattered and rescattered the blue light many times in many directions. Also, the surface of Earth has reflected and scattered the light. All this scattering mixes the colors together again so we see more white and less blue.
Any doubts?
Comment here...
http://www.facebook.com/atcdq