Particles And Radiation Flashcards
4 fundamental forces
- electromagnetic
- gravitational
- strong nuclear
-weak nuclear
Exchange particle of electromagnetic force
Virtual photom
Exchange particle of gravitational force
Graviton
Exchange particle (boson) of strong nuclear force
Gluon (it only acts for a short amount of time due to a very short half-life, so only acts through small distances. However, when the protons are too close proton repulsion happens)
Exchange particle of weak nuclear force
- W+ boson
- W- boson
- Z0 boson
Which forces can hadrons interact through
All 4 fundamental forces (can act through electromagnetic force if charged only)
Which forces can leptons act through
All fundamental forces, except strong nuclear, and only electromagnetic if charged
What are the 2 types of hadrons
Mesons and baryons
How many quarks in a meson
2 (quark antiquark)
How many quarks in a baryon
3
What mesons are there
π meson (pions):
π+, π-, π0
K meson (kaons):
K+, K-, K0
What are the types of baryons
P protons
n Neutrons
Σ Sigma
What are the types of leptons
e Electrons
Ve Electron Neutrino
µ- Muon
V µ Muon Neutrino
What is the only stable hadron
Proton
What is femto to the power of
10 to the power of -15
At what distances is the strong nuclear force repulsive/ attractive
-repulsive at separations up to 0.5fm
- then attractive up to a range of about 3fm.
- It has no effect after 3 fm
What are isotopes
Same number of protons, different number of neutrons
What does specific mean in physics
Per unit mass
What is an alpha particle
A helium nucleus
What is a beta particle
A fast moving electron
Electromagnetic repulsion
Electron capture/ electron proton collisions
Beta minus decay
Beta plus decay
Why are protons and neutrons not fundamental particles
They have quarks
What is a boson
An exchange particle
Muon decay
E=
Mc^2
Electron annihilation
Pair production
Kaon decay
What does the strong nuclear force act between
Hadrons
When is strangeness conserved
In a strong nuclear interaction
Why does diffraction of a particle change depending on its momentum
As momentum p = mv, a smaller momentum will result in a longer wavelength. The diffraction or spread of a wave passing through a slit depends on the wavelength- the longer the wavelength, the more the light spreads out.
What is threshold frequency
The minimum frequency of light required to equal the work function energy
Characteristic of a strange particle
Long lifetimes
Sigma particle qualities
Quark structure: uus
Charge: +1
Strangeness: -1
Baryon number: +1
What particles are fundamental
Leptons
What is a fundamental particle
a subatomic particle that has no other particles attached to it
Quark structure of a sigma baryon
suu
Practical application of annihilation
in a PET scanner
Exchange particle def
An exchange particle is a particle which gives rise to the force between two particles by acting as a carrier between them
annihilation def
When a particle meets its corresponding antiparticle they both are destroyed and their mass is converted into energy in the form of two gamma-ray photons
pair production def
When a photon interacts with a nucleus or atom and the energy of the photon is used to create a particle–antiparticle pair
properties of antiparticles
Corresponding matter and antimatter particles have
Opposite charges
The same mass
The same rest mass-energy
pair production diagram with nucleus
Why is there a value for maximum kinetic energy of an electron leaving a surface
Why are electrons emitted at discrete frequencies when they de-excite
What is stopping potential
As the electrons are charged, they must do work, e × Vs, to move through this potential. The electrons will stop if all their kinetic energy is used up doing work against the potential.
