:Note: This was a Topic I started, but I'll put it here too.

A central issue to many of the debates on the politics forum is energy - generation, limitations, or use. Yet many people have misconceptions or unanswered questions about what energy really is, and what all of the stories really means. This thread is created to serve as a reference, to make the political issues related to energy and power more clear and understandable.

What is energy?

Energy is the ability to change motion. Energy is the ability to stop a moving car, get up in the morning, or shoot a rocket into space. More interestingly, energy can be very quantitatively measured and calculated.

Objects have two kinds of energy: potential and kinetic. Kinetic energy is the motion of an object. Potential energy can be freely converted into kinetic energy, and kinetic can become potential.

How do we measure energy?

In the metric system, energy is measured in a basic unit called a "Joule".

If you want to experience what a joule is, take something that weighs one pound. Raise it 3 inches above the ground. Drop it. Congratulations, you have just converted one joule of gravitational energy into heat energy.

As you can probably tell, that's not a whole lot of energy. A joule is an extremely small unit of energy

Another nice place to see this in action is food. The Calorie is a unit of energy, and one calorie is 4184 Joules. Yep, that's the same Calorie you see on food labels. So in each day (assuming you follow the 2000 calorie a day guideline), you should consume about eight million joules of energy each day!

Is energy the same thing as electricity?

Electricity is an easy way to transport and use energy, but it is not the only form.

Are power and energy the same thing?

No, energy is a measure of the ability to change motion. Power is a measure of the change in energy.

What's a watt? Is a watt a measure of energy?

No, the watt is a measure of power. Power is energy per unit time: Joules per second, the same way speed is measured in miles per hour.

Speed is how much you change your position in a certain amount of time. Likewise, power is how much you change your energy in a certain amount of time.

So if a power plant makes 1000 KW, that means it makes 1 million joules of energy every second. (Remember that the K means multiply by 1000).

What's a volt? Is a volt a measure of energy?

No. Volts = energy per charge.

Is infrared radiation the same as heat?

No. Infrared radiation is a part of the electromagnetic spectrum.

Basically, when at atom gets excited, and full of energy, it sometimes will decide to give off electromagnetic radiation. The hottest molecules give off the highest energy radiation, while the cooler molecules give off lower energy radiation.

http://cdn.libsyn.com/astronomy/ems510 .jpg

What we call "light", is the part of the electromagnetic spectrum that our sun gives off. A hotter sun would give off higher energy radiation, and cooler objects give off lower energy radiation.

Normal, everyday objects, like you or me - are full of lots of excited little molecules. But since we're all a tad bit cooler than the sun, the radiation that we give off has less energy than the sun's visible light. So we give off infrared radiation.

Since everyday objects emit infrared radiation, it is a useful tool for finding heat. Infrared is caused by heat - it is not the same thing.

What is temperature?

Everything around you - even you! - is made up of lots of tiny molecules. But these molecules are not staying in position. Rather, they are rapidly moving and jiggling around - bumping into each other. Temperature is a measure of how much of this "jiggling" there is (per unit mass).

Can I build a perpetual motion device?

No. In a closed system, there's only a certain amount of kinetic and potential energy. Since energy can't come out of nowhere, eventually your device will start to decay until it is completely random.

If I have two magnets, and I let them fall towards each other, am I creating energy out of nothing?

No, the magnets have electromagnetic potential energy that is turned into kinetic energy when you let go and let them hit each other. To give them back that ability to cause motion, you'll have to move them apart, putting in your own energy.

In other words, they have potential energy, which can be converted into kinetic energy. To get them to create more kinetic energy, you'll have to bring in outside energy (maybe from your hand).

How do hydrocarbon (fossil fuels) work?

Oil, coal, or any of your other favorite fossil fuels are large molecules composed of hydrogen and carbon atoms.

These large molecules share amongst themselves many electrons, and have a great deal of electromagnetic potential energy (since electrons repel each other, and want to get farther apart).

In the presence of oxygen, these hydrocarbons break apart and form Carbon Dioxide and water. In the carbon dioxide and water molecules, the electrons get to be closer to the protons, and farther from other electrons. Because they get closer together, some of their electromagnetic potential energy is converted into kinetic energy (hence the reason why molecules undergoing combustion are very hot). Some of the energy is also converted into electromagnetic radiation (hence the reason why fires tend glow and emit light).

How does solar power work?

Since light (and all electromagnetic radiation for that matter)

How does hydroelectric (dam) power work?

Light from the sun strikes water molecules on the Earth. This electromagnetic potential energy (all light is, really) excites the water molecules, and turns them into gas (something we see as evaporation). With more kinetic energy, the water molecules bounce up towards the atmosphere, and eventually condense as clouds. When it rains, much of the water falls in the mountains, and flows downward into rivers. These rivers are dammed, and the water flowing down spins a turbine.

In short:

1. The electromagnetic energy of the sun's light is converted into kinetic energy for the water particles
2. The kinetic energy of the water particles is converted into gravitational potential energy
3. That is converted back into kinetic energy of flowing water
4. Electrical potential energy is generated by the turbines

How does nuclear fission work?

If you ever get the chance to look at a periodic table, you'll see that Plutonium and Uranium are extremely large and massive. The centers of Plutonium and uranium atoms are full of protons, which, as you remember, repel each other. This makes these molecules highly unstable, since they're composed of particles that are trying to get away. Imagine trying to stick the South ends of twenty magnets together, and you get the idea.

In high energy situations (nuclear bomb or power plant), the protons in the nucleus are able to escape. Since they are repelled by lots of other protons, they gain a lot of kinetic energy (speed). We see this as an explosion and a shockwave.

How does nuclear fusion work?

There is an attraction between protons and neutrons called the "Strong Nuclear Force". In small atoms like Hydrogen, where there is only one proton in the nucleus, the atom is actually somewhat unstable - since it mostly lacks this binding "glue".

Because of this, protons like to get closer to neutrons, the same way the Earth and the sun try to get closer together. Nuclear fusion is bringing two hydrogen atoms together and converting that potential attraction into motion.

This was intended to be written for a general audience. If anything was unclear or difficult to understand, please do not hesitate to inform me so I can work on correcting the problem. Also if I made any mistakes or errors, I apologize.

My email is Alex6200@gmail.com

alex6200@gmail.com