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Energy From the Atom
Or…
Energy From the Atom
Energy from the Atom
• Energy can be produced from either splitting atoms or combining them.
• Splitting atoms is called fission.
• Combining atoms is called fusion.
• Both produce enormous amounts of energy.
…fission has 2 “s” so it can be split.
Fission
• Fission is the splitting of an atom, usually, uranium, into smaller atoms.
• To do this, uranium is “bombarded” by neutrons.
• When the uranium splits into its smaller pieces, more neutrons are released.
• When the splitting occurs, the two pieces weigh slightly less than the original whole.
• This missing mass is turned into energy from Einstein’s equation E = mc2…a whole lot of energy!
• Some extra neutrons are also released
• Now, there are two ways you can go with this…
• When “bombarding” uranium with neutrons, do it slowly so only small amounts of “a whole lot of energy” are released.
• This is called a controlled reaction.
• Also, use water to keep it cool and avoid a meltdown.
• Absorb a lot of heat and the water boils, which turns a turbine to produce electricity.
• This is called nuclear energy.
#1
Three Mile Island, PA
Diablo Nuclear Power Plant, CA
• Notice that when uranium is bombarded by neutrons, that the reaction itself releases more neutrons.
• Also notice that these fresh neutrons are available to smack into other uranium atoms.
#2
• When this process is uncontrolled, or allowed to proceed quickly on its own, all that huge amount of energy is released at one time in a huge explosion.
• This is the how the atom bombs worked that were dropped on Japan during WW II.
• With great power comes great responsibility.
- Spiderman
• It should be noted that when some of the scientists (who developed the atom bomb) saw how much power was produced, they were sorry they had help develop it.
• Even Einstein wrote a letter to President Truman urging him not to use the weapon.
Nuclear Fusion
Nuclear Fusion• Atoms are combined (opposite of fission).
• 4 hydrogen atoms are combined to make a single helium atom.
• Once again, mass is lost in the process, and again, this mass is converted into energy in the form of energy packets called photons…more later.
• Fusion is how the sun produces energy.
• Occurs in the core of the sun (and all stars).
• Core temperature = 27 million degrees F …better bring your sunglasses!
• The internal pressure would make a bottle of Coke weigh about 175 pounds!
• Each second the sun produces more energy than all of mankind has used during all of its entire existence.
• Over 1 million Earths could fit into the sun.
• Emits all types of energy, from low energy radio waves to high energy gamma waves.
• Energy released in the form of photons.
• Fusion in the core makes energy, mostly in the form of light.
• This light has to work its way to the surface but the sun is tightly packed with material.
• The time light needs to reach the outside of the sun from the core is maybe 100,000 years.
• It takes only 8 m 19 s for sunlight to reach Mr. Earth.
• Light reaches Earth by traveling in “bundles” called photons.