Particles And Radiation 19-46 Flashcards
(43 cards)
What’s a nucleon?
Protons and neutrons
How is specific charge calculated?
Specific charge = Charge / Mass
What is specific charge?
The charge to mass ratio of a particle
What’s an isotope?
An atom with the same number of protons but a different number of neutrons
How does the strong nuclear force keep nuclei stable?
By counteracting the electrostatic force of repulsion between protons in the nucleus (as they have the same charge)
When is the SNF repulsive?
0-0.5 fm
When is the SNF attractive?
Between 0.5-3 fm
What happens to the strong nuclear force after 3 fm?
It is not attractive or repulsive
Why do nuclei decay?
When it has too many protons, neutrons or both which causes SNF to not be enough to keep them stable, therefore these nuclei will decay in order to become stable
When does alpha decay occur?
Large nuclei with too many protons and neutrons
What happens in alpha decay?
An alpha particle (helium nucleus) is produced and the particle decays accordingly
When does beta-minus decay occur?
Nuclei which are neutron-rich (have too many neutrons)
What happens in beta-minus decay?
A beta particle (electron) is produced along with an anti neutrino and the particle decays accordingly
What’s the antiparticle of an electron and neutrino?
The positron and the anti neutrino
What’s a photon?
Electromagnetic radiation that travels in pockets
What’s annihilation?
Where a particle and its corresponding antiparticle collide
What happens in annihilation?
The particles’ masses are converted into energy, this energy, along with the kinetic energy of the two particles is released in the form of 2 photons moving in opposite directions in order to conserve momentum.
Whats pair production?
Where protons collide or a photon is converted into an equal amount of matter and antimatter
When does pair production occur?
When the photon has an energy greater than the total rest energy of both particles, any excess energy is converted into kinetic energy of the particles
What are the 4 fundamental forces?
Gravity, electromagnetic, weak nuclear and strong nuclear
How do these forces occur?
Exchange particles carry energy and momentum between the particles experiencing the force and each fundamental force has its own exchange particles
Name the exchange particle and what it acts on: SNF
Gluon, hadrons
Name the exchange particle and what it acts on: WNF
W boson ( W + or W − ), all particles
Name the exchange particle and what it acts on: Electromagnetic force
Virtual photon ( γ ), charged particles