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Gravitational Potential and Kinetic Energy | GCSE Physics | Doodle Science

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Ball pendulum

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A roller coaster going up

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Nagashima Spaland Japan Togo Heartline Coaster

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Green Lantern POV Roller Coaster Front Seat Six Flags Great Adventure New Jersey SFGadv

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Shock Wave Roller Coaster POV Stand Up Front Seat View Onride Drayton Manor UK England

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Roller Coasters in the RAW DVD Series available at Amazon! Filmed & Edited by Robb Alvey - http://www.themeparkreview.com

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A spring in a pen

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trampoline

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Rubber band

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A rubber band is a loop of rubber, usually ring shaped, and commonly used to hold multiple objects together. The rubber band was patented in England on ...

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Is energy that is generated by magnetic waves

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Wind energy is energy that is powered by the wind

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Hydropower is energy that is generated by moving water

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Hydropower is electricity generated using the energy of moving water. Rain or melted snow, usually originating in hills and mountains, create streams and rivers that eventually run to the ocean. The energy of that moving water can be substantial, as anyone who has been whitewater rafting knows.

Humans have been taking advantage of this source of energy for centuries. Farmers since the ancient Greeks have used water wheels to grind wheat into flour. Placed in a river, a water wheel picks up flowing water in buckets located around the wheel. The kinetic energy of the flowing river turns the wheel and is converted into mechanical energy that runs the mill.

In the late 19th century, hydropower became a source for generating electricity. The first hydroelectric power plant was built at Niagara Falls in 1879. In 1881, street lamps in the city of Niagara Falls were powered by hydropower. In 1882, the world's first hydroelectric power plant began operating in the United States in Appleton, Wisconsin.

How it Works

A typical hydro plant is a system with three parts: an electric plant where the electricity is produced, a dam that can be opened or closed to control water flow, and a reservoir where water can be stored. The water behind the dam flows through an intake and pushes against blades in a turbine, causing them to turn. The turbine spins a generator to produce electricity. The amount of electricity that can be generated depends on how far the water drops and how much water moves through the system. The electricity can be transported through long-distance electric lines to homes, factories, and businesses.

Where It's Used

Hydroelectric power provides almost one-fifth of the world's electricity. China, Canada, Brazil, the United States, and Russia were the five largest producers of hydropower in 2004. One of the world's largest hydro plants is at Three Gorges on China's Yangtze River. The dam is 1.4 miles (2.3 kilometers) wide and 607 feet (185 meters) high.

The biggest hydro plant in the United States is located at the Grand Coulee Dam on the Columbia River in northern Washington. More than 70 percent of the electricity made in Washington State is produced by hydroelectric facilities.

Hydropower is the cheapest way to generate electricity today. That's because once a dam has been built and the equipment installed, the energy source-flowing water-is free. It's a clean fuel source that is renewable yearly by snow and rainfall. Hydropower is also readily available; engineers can control the flow of water through the turbines to produce electricity on demand. In addition, reservoirs may offer recreational opportunities, such as swimming and boating.

But damming rivers may destroy or disrupt wildlife and other natural resources. Some fish, like salmon, may be prevented from swimming upstream to spawn. Technologies like fish ladders help salmon go up over dams and enter upstream spawning areas, but the presence of hydroelectric dams changes their migration patterns and hurts fish populations. Hydropower plants can also cause low dissolved oxygen levels in the water, which is harmful to river habitats.

Some researchers believe the strain dams impose on the environment make this method of energy production more trouble than it's worth. A study in the journal BioSciences found that the reservoirs created by dams pollute methane, a greenhouse gas, into the atmosphere as a result of the breakdown of organisms in now stagnant pools of water.

In addition to environmental concerns, dams also pose a strain on the communities around them. The Three Gorges dam on China's Yangtze River displaced an estimated 1.3 million people and flooded thousands of villages.

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hydro hydropower hydroelectricity alternative energy turbines irrigation tidal wave waterwheels electric power generation dams fossil fuels

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Hydropower is electricity generated using the energy of moving water. Rain or melted snow, usually originating in hills and mountains, create streams and rivers that eventually run to the ocean. The energy of that moving water can be substantial, as anyone who has been whitewater rafting knows.

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This is a website on Gravitational energy and provides all the information for gravitational information

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What is gravitational and potential energy?

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Find out the difference between potential and gravitational energy. See examples of how energy is transferred into an object and kept high to defy gravity. What happens if the object falls. Gravitational energy is released into kinetic energy. Let see this example.

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This video show how elastic energy works in a cartoon

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Potential Energy: Wile E Coyote & Roadrunner

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This is website on Mechanical energy and how Kinetic and Mechanical are the same

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Mechanical energy: Mechanical energy, sum of the kinetic energy, or energy of motion, and the potential energy, or energy stored in a system by reason of the position of its parts.

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This website explains to us about nuclear energy

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Nuclear energy is the energy in the nucleus, or core, of an atom. Atoms are tiny units that make up all matter in the universe. Energy is what holds the nucleus together. There is a huge amount of power in an atoms dense nucleus. In fact, the power that holds the nucleus together is officially called the " strong force.

Nuclear energy can be used to create electricity, but it must first be released from the atom. In nuclear fission, atoms are split to release the energy.

A nuclear reactor, or power plant, is a series of machines that can control nuclear fission to produce electricity. The fuel that nuclear reactors use to produce nuclear fission is pellets of the element uranium. In a nuclear reactor, atoms of uranium are forced to break apart. As they split, the atoms release tiny particles called fission products. Fission products cause other uranium atoms to split, starting a chain reaction. The energy released from this chain reaction creates heat.

The heat created by nuclear fission warms the reactors cooling agent. A cooling agent is usually water, but some nuclear reactors use liquid metal or molten salt. The cooling agent, heated by nuclear fission, produces steam. The steam turns turbines, or wheels turned by a flowing current. The turbines drive generators, or engines that create electricity.

Rods of material called nuclear poison can adjust how much electricity is produced. Nuclear poisons are materials, such as a type of the element xenon, that absorb some of the fission products created by nuclear fission. The more rods of nuclear poison that are present during the chain reaction, the slower and more controlled the reaction will be. Removing the rods will allow a stronger chain reaction and create more electricity.

About 15 percent of the worlds electricity is generated by nuclear power plants. The United States has more than 100 reactors, although it creates most of its electricity from fossil fuels and hydroelectric energy. Nations such as Lithuania, France, and Slovakia create almost all of their electricity from nuclear power plants.

Nuclear Food: Uranium

Uranium is the fuel most widely used to produce nuclear energy. Thats because uranium atoms split apart relatively easily. Its also a very common element, found in rocks all over the world. However, the specific type of uranium used to produce nuclear energy, called U-235, is rare. U-235 makes up less than one percent of the uranium in the world.

Although some of the uranium the United States uses is mined in this country, most is imported. The U.S. gets uranium from Australia, Canada, Kazakhstan, Russia, and Uzbekistan. Once uranium is mined, it must be extracted from other minerals. It must also be processed before it can be used.

Because nuclear fuel can be used to create nuclear weapons as well as nuclear reactors, only nations that are part of the Nuclear Non-Proliferation Treaty (NPT) are allowed to import uranium or plutonium, another nuclear fuel. The treaty promotes the peaceful use of nuclear fuel, as well as limiting the spread of nuclear weapons.

A typical nuclear reactor uses about 200 tons of uranium every year. Complex processes allow some uranium and plutonium to be re-enriched or recycled. This reduces the amount of mining, extracting, and processing that needs to be done.

Nuclear Energy and People

Nuclear energy produces electricity that can be used to power homes, schools, businesses, and hospitals. The first nuclear reactor to produce electricity was located near Arco, Idaho, in the U.S. The Experimental Breeder Reactor began powering itself in 1951. The first nuclear power plant designed to provide energy to a community was established in Obninsk, Russia, in 1954.

Building nuclear reactors requires a high level of technology, and only the countries that have signed the Nuclear Non-Proliferation Treaty can get the uranium or plutonium that is required. For these reasons, most nuclear power plants are located in the developed world.

Nuclear power plants produce renewable, clean energy. They do not pollute the air or produce greenhouse gases. They can be built in urban or rural areas, and do not radically alter the environment around them.

The steam powering the turbines and generators is ultimately recycled. It is cooled down in a separate structure called a cooling tower. The steam turns back into water and can be used again to produce more electricity. Excess steam is simply recycled into the atmosphere, where it does no harm as clean water vapor.

However, the byproduct of nuclear energy is radioactive material. Radioactive material is a collection of unstable atomic nuclei. These nuclei lose their energy and can affect many materials around them, including organisms and the environment. Radioactive material can be extremely toxic, causing burns and increasing the risk for cancers, blood diseases, and bone decay.

Radioactive waste is what is left over from the operation of a nuclear reactor. Radioactive waste is mostly protective clothing worn by workers, tools, and cloths that have been in contact with radioactive dust. Radioactive waste is long-lasting. Materials like clothes and tools can stay radioactive for thousands of years. The government regulates how these materials are disposed of so they dont contaminate anything else.

Used fuel and rods of nuclear poison are extremely radioactive. The used uranium pellets must be stored in special containers that look like large swimming pools. Water cools the fuel and insulates the outside from contact with the radioactivity. Some nuclear plants store their used fuel in dry storage tanks above ground.

The storage sites for radioactive waste have become very controversial in the United States. For years, the government planned to construct an enormous nuclear waste facility near Yucca Mountain, Nevada, for instance. Environmental groups and local citizens protested the plan. They worried about radioactive waste leaking into the water supply and the Yucca Mountain environment, about 130 kilometers (80 miles) from the large urban area of Las Vegas, Nevada. Although the government began investigating the site in 1978, it stopped planning for a nuclear waste facility in Yucca Mountain in 2009.

Chernobyl

Critics of nuclear energy worry that the storage facilities for radioactive waste will leak, crack, or erode. Radioactive material could then contaminate the soil and groundwater near the facility. This could lead to serious health problems for the people and organisms in the area. All communities would have to be evacuated.

This is what happened in Chernobyl, Ukraine, in 1986. A steam explosion at one of the power plants four nuclear reactors caused a fire, called a plume. This plume was highly radioactive, creating a cloud of radioactive particles that fell to the ground, called fallout. The fallout spread over the Chernobyl facility, as well as the surrounding area. The fallout drifted with the wind, and the particles entered the water cycle as rain. Radioactivity traced to Chernobyl fell as rain over Scotland and Ireland. Most of the radioactive fallout fell in Belarus.

The environmental impact of the Chernobyl disaster was immediate. For kilometers around the facility, the pine forest dried up and died. The red color of the dead pines earned this area the nickname the Red Forest. Fish from the nearby Pripyat River had so much radioactivity that people could no longer eat them. Cattle and horses in the area died.

More than 100,000 people were relocated after the disaster, but the number of human victims of Chernobyl is difficult to determine. The effects of radiation poisoning only appear after many years. Cancers and other diseases can be very difficult to trace to a single source.

Future of Nuclear Energy

Nuclear reactors use fission, or the splitting of atoms, to produce energy. Nuclear energy can also be produced through fusion, or joining (fusing) atoms together. The sun, for instance, is constantly undergoing nuclear fusion as hydrogen atoms fuse to form helium. Because all life on our planet depends on the sun, you could say that nuclear fusion makes life on Earth possible.

Nuclear power plants do not have the capability to safely and reliably produce energy from nuclear fusion. Its not clear whether the process will ever be an option for producing electricity. Nuclear engineers are researching nuclear fusion, however, because the process will likely be safe and cost-effective.

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Part of Speech

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salt

Noun

(sodium chloride, NaCl) crystalline mineral often used as a seasoning or preservative for food.

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Nuclear energy is the energy in the nucleus, or core, of an atom. Atoms are tiny units that make up all matter in the universe. Energy is what holds the nucleus together. There is a huge amount of power in an atoms dense nucleus.

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This website explains to us everything we need to know about Chemical energy

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What Is Chemical Energy?

Energy is the ability to do work, where work is movement of an object by some force. We use energy every day, and energy comes in different forms. Chemical energy is energy that is stored in chemicals, such as sugar and gasoline. As chemical energy is stored energy, it is a type of potential energy, which is energy stored in objects due to their location. An easy example of potential energy would be that of a bike on top of a hill where the bike's position is elevated and has the ability to roll down the hill. In the case of chemicals, the position refers to the various atoms that exist together within the chemical.

Application of Chemical Energy

Now that we understand that chemicals contain potential energy, let's explore the significance of chemical energy. In other words, what does chemical energy do for nature?

Let's play a word association game. What do you think of when I say 'The Circle of Life'? If you're like me, you probably thought of the Disney movie 'The Lion King'. Man that was a great movie! Another way of thinking about the circle of life is in terms of energy utilization within nature. Let me explain. Plants use energy from the sun to make sugar and oxygen from carbon dioxide and water. We, along with other animals, digest that sugar to release energy, so we can do work. Sugar is digested; in other words it's broken down, into carbon dioxide and water, which, in turn, is used by plants to make more sugar.

Are you getting the circle of life?

Chemical Energy in Everyday Life

We just talked about the fact that plants use solar energy to make sugar from carbon dioxide and water. Sugar, carbon dioxide and water are all chemicals that are held together by what we call chemical bonds or forces that hold the chemicals together. For example, all sugars are composed of carbon, oxygen and hydrogen atoms that are held together by chemical bonds. These atoms don't just stick together automatically. Rather, energy is needed to hold them together. Plants utilize solar energy to put the carbon, the hydrogen and the oxygen atoms together in the form of sugar. This is a really good example of energy transformation where energy is changed from one form to another. In this case, solar energy is converted into chemical energy that holds the sugar together and prevents it from falling apart.

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what is chemical energy? - definition & examples - video & lesson transcript | study.com

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What is Chemical Energy? - Definition & Examples - Video & Lesson Transcript | Study.com

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Energy is the ability to do work, where work is movement of an object by some force. We use energy every day, and energy comes in different forms. Chemical energy is energy that is stored in chemicals, such as sugar and gasoline.

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This video shows us how Sound travels and how you can hear sound

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How sound energy is measured and basic vocabulary used to describe characteristics. Thanks to Sid the Science Kid for the song that is included.

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This is electric energy and it shows how electricity powers things

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This shows how light energy give light and you are able to see things

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Çocuk çizgi film animasyon. What is Energy Types of Energy Light Energy Kids learning Animation Video Tutorial