Chapter 18 Flashcards
Describe “The Nuclear Model” (Rutherford’s Model) 4 Points.
Atom is mostly empty space.
Centre of the atom has a large positive charge (Nucleus).
The nucleus is tiny.
Most of the mass is in the nucleus.
How can you estimate the closest approach of a scattered particle?
- Electric potential energy=Initial kinetic energy.
- Rearrange the equation (EPE) to make r the subject.
- The charge on a proton is +e so multiply that by the proton number of the nucleus. (Charge of an alpha particle is +2e).
- Press =!
What are Hadrons?
Particles that feel the strong interaction. (e.g. Protons and Neutrons)
What is the only stable Hadron?
The Proton.
What are Leptons?
Particles that don’t feel the strong interaction. (e.g. Electrons and Neutrinos)
What is the difference between a particle and its corresponding anti-particle?
The relative charge is opposite. Mass stays the same.
What are the decay products of a (free) neutron?
Proton+Electron+Antineutrino
What is made when energy is converted into mass?
Equal amounts of matter and antimatter.
What happens when a particle meets its anti-particle?
Annihilation. (All mass gets converted into energy)
What can a cloud chamber be used for?
To observe pair production and annihilation.
What are Quarks?
Fundamental particles. Building blocks for Hadrons.
In a reaction what must be conserved?
Charge and Lepton number.
How many Quarks make up Protons and Neutrons?
Three.
What do Gluons do?
Provide force between Quarks.
What do particle accelerators do?
Cause high-energy collisions.
