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UPRM Center. Rafael Aramis López LEAD TEACHER. UPRM Center. QuarkNet is a teacher professional development program funded by the National Science Foundation and the US Department of Energy. . UPRM Center.
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UPRM Center Rafael Aramis López LEAD TEACHER
UPRM Center QuarkNet is a teacher professional development program funded by the National Science Foundation and the US Department of Energy.
UPRM Center QuarkNet brings high school students and teachers to the frontier of 21st century research that seeks to research some of the mysteries about the structure of matter and the fundamental forces of nature.
UPRM Center • Physicists mentor collaborate • with high school teachers. • Teachers join research teams • with physicists at a local • university or laboratory. • Students learn fundamental • physics as they analyze live • online data and participate in • inquiry-oriented investigations.
Active QuarkNet Centers UPRM Center Nosotros Nosotros Active QuarkNet Centers
QuarkNet centers are connected to high-energy physics experiments operating at CERN in Switzerland, at Fermilab in Illinois, at SLAC in Califormia and others. Within two years, we expect to form 60 centers associated with research groups at universities and labs across the U.S.
People have long asked, "Of what is the world made?" and "What holds it together?" • The word "fundamental" is key here. • By fundamental building blocks we mean objects that are simple and structureless - not made of anything smaller.
The ancient Greeks (@400 B.C.) are recognized for theearliest attempts to describe the microstructure of ourUniverse • All substances were made of a basic • kind of matter called hulè. • Matter is continuous and is made of • different combinations of 4 things: • earth, fire, air, and water. • Aristotle’s major criticisms concerned • the idea that atoms moved through • empty space. Democritus
The ancient Greeks (@400 B.C.) are recognized for theearliest attempts to describe the microstructure of ourUniverse • Matter is made up of tiny individual particles • he named atomos. • Atomos could not be created, destroyed or • further divided. • Matter is also composed of empty space • through which atoms moved. • All substances were made of a basic • kind of matter called hulè. • Matter is continuous and is made of • different combinations of 4 things: • earth, fire, air, and water. • Aristotle’s major criticisms concerned • the idea that atoms moved through • empty space. Democritus
LEVITY FORCE HOT MOIST COLD DRY GRAVITY FORCE ARISTOTLE’S MATTER CONCEPT
ANTOINE LAVOISIER The father of the chemistry Considered as the predecessor of the modern chemistry, there realized one of the most important discoveries of this one science, theLaw of the Conservation of the Mass.
3. Atoms of a given element are different from those of any other element 4. Atoms of one element combine with atoms of other elements to form compounds. 5. Atoms are indivisible in a chemical process. 2. All atoms of a given element are identical 1. Elements are composed of atoms Dalton's Atomic Theory
DISCOVERY OF THE ELECTRON In 1897, Joseph JohnThompson discovered the first component partof the atom: the electron, a particle with a negative electric charge. In 1904, he proposed an initial model of an atom, since nicknamed "Thompsons pudding". He imagined the atom as a sphere full of an electrically positive substance mixed with negative electron "like the raisins in a cake".
DISCOVERY OF THE NUCLEUS Ernest Rutherford discovered that the atom is mostly empty space with a dense positively charged nucleus surrounded by negative electrons The electron in an atom moves around this nucleus like planets around the Sun; which is where we get the name “Theatomic planetary model"..
BOHRS ATOM In 1913 NielsBohr created a new model of the atom: The orbits of the electrons can't be just anywhere but are "quantified"; only certain particular orbits are permitted for the electron.
DISCOVERY OF NUCLEONS • Rutherford understood that the nucleus is itself • composed of nucleons. These nucleons are of two types: • positively charged, it's a proton. • neutrally charged, it's a neutron • The neutron was discovered in 1932 by JamesChadwick.
The Charge-Cloud Model The charge-cloud model, which is also called the quantum-mechanical model, does not attempt to describe the path of each electron in a fixed orbit. Scientists now describe the possible positions of electrons in terms of probability.
Physicists have discovered that protons and neutrons are composed of even smaller particles called quarks. As far as we know, quarks are like points in geometry. They're not made up of anything else.
If the protons and neutrons were a centimeter in diameter; Then the electrons and quarks would be less than the diameter of a hair; and The entire atom's diameter would be greater than the length of 30 football fields! 99.99% of the atom is empty space THE MODERN ATOM MODEL
Physicists have developed a theory called The Standard Model that explains what the world is and what holds it together. It is a simple and comprehensive theory that explains all the hundreds of particles and complex interactions with only: • 6 quarks. • 6 leptons. The best-known lepton is the electron. • Force carrier particles, like the photon. THE STANDARD MODEL
The Universe is made of Quarks and Leptons Everything from galaxies to mountains to molecules is made from quarks and leptons. Quarks behave differently than leptons, and for each kind of matter particle there is a corresponding antimatter particle.
Matter and Antimatter For every type of matter particle we've found, there also exists a corresponding antimatter particle, or antiparticle. Antiparticles look and behave just like their corresponding matter particles, except they have opposite charges.
Quarks are one type of matter particle. Most of the matter we see around us is made from protons and neutrons, which are composed of quarks.
BARYONS qqq 1+ + + = electric charge THE PROTON
BARYONS qqq 0 + + = electric charge THE NEUTRON
MESONS qq anti 1+ + = electric charge THE PION ( π+)
ANTIBARYONS qqq anti anti anti 1- + + = electric charge THE ANTIPROTON
There are six leptons, three of which have electrical charge and three of which do not. They appear to be point-like particles without internal structure. The best known lepton is the electron.The other leptons are the three types of neutrinos. They have no electrical charge, very little mass. LEPTONS
What Powers the Sun? Its Source of Energy The Sun is a big thermonuclear reactor that works by converting hydrogen into helium. Gravitational Contraction? Chemical Reaction?
The Sun’s Interior The Core, at about 15,000,000 K, is the source of the Sun’s energy. The site of the thermonuclear fusion.
Its Source of Energy Thermonuclear Fusion Reaction 4 1H --> 4He +energy Energy Produced = 0.007(mass of 4 1H)c2
Solar Energy Production To get the positively-charged nuclei to fuse together, their electrical repulsion must be overcome.
Solar Energy Production 1 2 4 3
Mass to Energy! One helium nucleus has 99.3% of the weight of four hydrogen nuclei. This excess of 0.7% of hydrogen mass compared with helium mass is converted into energy. We can calculate the amount of energy create from the excess of mass by using E=mc2. The creation of each helium nucleus requires four hydrogen nuclei.
Solar Energy Production The net result is 6 1H + 2 e --> 4He + 2 1H + 2 neutrinos + 6 photons or 4 1H + 2 e --> 4He + 2 neutrinos + 6 photons The net energy release is 26 MeV!
Alaska's glaciers are receding at twice the rate previously thought, according to a new study published in the July 19, 2002 Science journal. These two images show Portage Glacier, near Anchorage, Alaska, in 1914 and in 2004. The ice has pulled back nearly out of sight.