Learning Goals: 4. Complex Knowledge: demonstrations of learning that go aboveand above and beyond what was explicitly taught. 3. Knowledge: meeting the learning goals and expectations. 2. Foundational knowledge: simpler procedures, isolated details, vocabulary. 1. Limited knowledge: know very little details but working toward a higher level. How do stars differ from moons and planets, and from one another? How does the classification of stars help us understand how they evolve over their lifetimes? What are the different types of stars? What happens when different types of stars die? Why is it important for us to understand stars?

Nuclear Fusion – Today’s Questions What is the process that powers stars? What are the important characteristics of the process that powers stars?

Question… There are 4 Questions at each group. Middle name comes first in alphabet: Penny Middle name comes second in alphabet : Coal Middle name comes third in alphabet : House Middle name comes last in alphabet : Paperclip In your notebook, answer your questions and explain why/how you arrived at your answer

E=mc2 One of the most extraordinary things about Einstein’s energy-mass equation is its simplicity. However, we still need to make sure we are using the correct units when solving the equation, and that we understand the answer

E=mc2 E = energy (measured in joules) m = mass (measured in kilograms) If we break the equation E = mc2 into its components and write out the terms fully we get: E = energy (measured in joules) m = mass (measured in kilograms) c = the speed of light (3 x 108 m/s or 186,000 miles per second)

Solving the equation… mass = 1kg 90,000,000,000,000,000 joules

A huge amount of energy can be produced by a small amount of mass. the equation is very easy to solve, and it shows that even a small amount of mass can release a huge amount of energy. E = mc2 A huge amount of energy can be produced by a small amount of mass.

Revisit your question OR Using E=mc2 Revise your answer and explain why you revised it. OR Explain why you think your answer is correct.

It's true. If you could harness its power—that is, turn every one of its atoms into pure energy—the paper clip would yield about 18 kilotons of TNT. That's roughly the size of the bomb that destroyed Hiroshima in 1945. In the Hiroshima explosion, countless atoms of uranium were split apart in a nuclear chain reaction. Each time an atom split, the total mass of the fragments speeding apart was less than that of the original atom. The bomb, in essence, transformed three- hundredths of an ounce of mass into a cataclysmic burst of heat and light.

Yes. If every grain became energy, the lump would yield around 25 billion kilowatt-hours— enough to keep the bulb glowing for about 29 million years. Burning the coal in a conventional power plant, by contrast, produces only enough energy to keep the bulb shining for 67 hours. In an Einsteinian dream world, power generation could be billions of times more efficient than ordinary combustion—and leave behind no ash or smoke!

Correct. Of course, on Earth there is no practical way to convert pennies, paper clips, or other objects entirely to energy. It would require temperatures and pressures greater than those at the core of our sun. In theory, though, a half dollar's worth of change could satisfy all of New York State's energy needs for about 1 day. Humankind uses so much energy in a month that it would take about 1,000 pounds worth of change.

Yes, and it probably wouldn't even take a McMansion Yes, and it probably wouldn't even take a McMansion. People in the business of relocating entire houses estimate that a 3,000-square-foot house weighs about 60 tons. Transformed entirely to energy, such a house would yield the equivalent of about 1,170,000 megatons of TNT, which would be roughly 65 million times more powerful than the bomb that fell on Hiroshima. This is far more energy than would be needed to melt half the ice in Antarctica—and possibly enough to split Earth in half

That's right. Two hundred million electron volts couldn't even boil a thimbleful of water but would likely kill an amoeba. Splitting a single atom of uranium yields a tiny amount of energy. When we speak of the awesome "power of the atom," we are generally referring to chain reactions involving as many as one septillion atoms—that's 1 followed by 24 zeros!

What does this have to do with stars?

Which element has the… Highest binding energy? Lowest? Binding energy of 5.5? Binding energy of 8? What happens to binding energy as the atomic mass of an element increases?

Binding energy = nuclear potential energy The greater the forces that hold particles together, the more difficult it is to tear the nucleus apart. Small nuclei will try to create other nuclei that are more stable by combining (or increasing the binding energy) The process of combining nuclei is called nuclear fusion

Fusion Only occurs at very high temperatures Only occurs at very high pressures 4 H to 1 He = 1 million degrees 3 He to 1 C = 10 million degrees Many C to N,O, and others = 100 million degrees

Modeling fusion