Go to the Particle Adventure Homepage (http://particleadventure.org/particleadventure/). Somewhere on these pages are the answers to the following questions. First concentrate on the sections "What is fundamental", "What is the world made of" and "What holds it together".

1. What is the "Standard Model"?



2. For how many years have physicists known that there were more than just protons, neutrons, electrons, and photons? 5? 25? 60? 100? 



3. How many quarks are there, what are their names, and when were the last three discovered?





4. What are hadrons, baryons, and mesons?




5. What are leptons?




6. How are quarks held together?




7. Now read the section on "Particle decays and annihilation". What are the types of radioactive particles?



8. What is "missing mass"? Where does it go?



9. What happens when electrons and positrons collide?



10. Read the section on "How do we experiment with tiny particles". What are the different types of accelerators? 



11. What is "The Event" that particle physicists are interested in when they do experiments?



12. What are three of the world's major accelerators, where are they, and roughly how large are they? Click on the links to see photos or drawings of the facilities.