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Why is the velocity faster on the outside bend of a meander?

As a general rule, a river's current flows fastest where the channel is deepest and there are the fewest obstructions. When a riverbed contains a meander, the water moves in what is known as a helicoidal flow. In a helicoidal flow the main current corkscrews from one side of the river to the other, creating more erosion and carving out a deeper channel on the outside of the meander. On the inside of the meander, there is less erosion and a shallower riverbed. Because of this structure, the water on the outside of the meander has the deepest channel and the least friction, which causes it ..

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How many satellites does Jupiter have?

Jupiter's moons have orbital spans that range from 7 hours to approximately 3 years. Some moons orbit in a circular fashion, while the ones farthest out maintain more unusual orbits. The outermost 33 moons have orbits that are opposite Jupiter's orbit, indicating that these satellites were originally asteroids that became trapped by Jupiter's gravity.\nThe Galilean satellites orbit closer to the planet. Ganymede is the largest moon in the solar system, and has its own magnetic field. Io was the first moon discovered by Galileo, and it is around the same age as Jupiter.

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What are some of the uses of alkanes?

Alkanes are hydrocarbons and consist only of carbon and hydrogen. The number of carbon atoms within an alkane determines its use. Propane, butane and methane, for example, are cooking and heating fuels, and are also used to generate electricity in some countries. Butane is used in disposable cigarette lighters. Under relatively low pressure, butane and propane can be liquified, and are then known as LPG, or liquid petroleum gas. These two alkanes are also used in aerosol sprays as propellants. Some alkanes with a higher number of atoms form the greater part of aviation and diesel fuel. These a..

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What are the types of mechanical weathering?

Mechanical weathering is similar to chemical weathering, and their effects sometimes overlap. Abrasion is the process in which an external force such as water movement or gravity causes rock material to grind together, which may break apart the outer layers of the affected rock. Mechanical exfoliation, or pressure release jointing, occurs when layers of rock parallel to surface ground are exposed, causing them to expand and break apart in rows.\nThermal fractioning occurs when extreme temperature changes cause the rock to expand or alter its chemical structure, which weakens the rock and break..

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What do humans need to survive?

Water is an essential part of survival, and the Mayo Clinic shows evidence to suggest that men need up to 3 liters per day while women need 2.2 liters per day. The Mayo Clinic also states that without an adequate amount of water, the body can become dehydrated and unable to carry out normal functions. Food is also necessary for the body to keep going, as it helps to absorb nutrients for energy, according to English Online. Food helps the body repair muscles, fight off diseases and stay healthy.\nAir, or oxygen, is what humans need in order to be able to breathe. The oxygen humans intake helps ..

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How are blizzards predicted or forecast?

The heavy snowfall that blizzards create can be hard to predict in advance. A computer model might indicate a potentially wet weather system moving into an area, and it might indicate temperatures falling into a range that could produce significant amounts of snow. However, the exact timing of these weather events can mean the difference between feet of snow and a cold, wet rain.\nIn addition, a storm moving into an area that has already seen heavy snowfall can create a ground blizzard, as high winds blow loose snow and create dangerous conditions. For this reason, the National Weather Service..

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How many teaspoons are in a coffee scoop?

Coffee is a very popular brewed drink that is made from water and roasted coffee beans. It contains a significant amount of caffeine, which makes the drink most commonly consumed in the morning. It was first introduced in the Middle East during the 15th century, and it can now be found in every country in the world. Countries in Asia, Africa, Europe and the Americas all grow their own style of coffee beans and export it as a primary source of revenue.While coffee was originally served hot, many different drinks containing coffee have been created that are both hot and cold. The most common add..

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How do you find an answer key for a Holt biology book?

As of 2015, Holt McDougal prints answers to all the questions in its textbooks, and it also offers extensive materials online through its book access portal. Access to these answers requires teacher or student login credentials, which are typically granted by school administrators or the publisher directly. For essay or paragraph answers, the book offers suggested or generic answers rather than exact responses.\nAmazon.com offers teacher editions of Holt biology books at a discount through individual sellers. The prices of these textbooks are typically less than new books from the publisher. H..

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Is coal a fossil fuel?

Coal is formed when organic plant matter is buried and compacted into a solid form over a long period of time. Prior to forming into coal, the organic plant matter takes form as a soft layer known as peat, which may be used as a fuel source. Coal has several forms, such as anthracite, bituminous and brown, with differing energy outputs. It is typically mined from underground deposits and through strip-mining. These mining practices have harmful effects on the environment if used extensively.

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What are some of the pros and cons of space exploration?

Many technologies developed by NASA and other space exploration agencies have found uses on Earth. Since 1973, NASA has published more than 1,800 reports highlighting technologies it has created or helped to develop. Today, satellite technology provides the backbone for GPS navigation systems, weather prediction, storm tracking and much of the world's communications network. However, private enterprise might have developed these technologies and launched satellites at less cost to taxpayers.\nMore than 20 astronauts have been killed during spaceflight missions, while others were killed pe..

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