Particles And Radiation Flashcards
(20 cards)
What’s the specific charge of a particle
Ratio of its charge to mass
What can isotopic data for the amount of carbon-14 in organic matter be used for
Calculate ge of archeological finds
What does the strong nuclear force do
Balances the electrostatic repulsion between protons and holds the nucleus together
What kind of nuclei emit nuclear radiation
Unstable atomic nuclei to become more stable
Describe an alpha particle
2 protons
2 neutrons
Describe a beta particle
Fast moving electron and an antineutrino
Describe a gamma ray
Short wavelength
High frequency
EM radiation
State the change when a beta radiation is emitted
Neutron changes to proton
Nucleon number stays same
Proton number decreases by one
What change occurs in a nucleus when gamma ray is emitted
The nucleus loses energy
What’s the penetrating power of beta radiation
Stopped by a few mm of aluminium
What are the two key properties of the neutrino
No charge
Very little mass
What’s the rest energy equal to when a particle is stationary
It’s rest mass
How many joules in one electron volt
1.6 x 10^-19
What are the properties of a particles antiparticle
Same rest mass
Opposite charge
What happens when a particle meets its antiparticle
Annihilation- all the mass of the particles is converted into photons of EM radiation
How many photons are released in annihilation
At least 2 because just one would not allow momentum to be conserved
Give a practical application of annihilation
Positron emission tomography scanners
What is pair production
Opposite process to annihilation where EM radiation in the form of a gamma photon is converted into matter (particle-antiparticle pair)
Name the 4 fundamental interactions
Gravity
EM
Weak nuclear
Strong nuclear
What are exchange particles
Particles that travel between two particles when they excert a force on each other
