Particles and Radiation Flashcards
What is the charge of a proton?
+1.60x10^-19 C
What is the specific charge of an electron?
-1.60x10^-19 C
What is the mass of an electron?
9.11x10^-31 kg
What is the mass of a nucleon?
1.67x10^-27 kg
What is ‘specific charge’?
Specific charge = ratio of charge to the mass of an atom
State the units of specific charge
C kg-1
Why do we use ‘relative charge’ instead of actual charge?
The charge and mass of atomic particles are really tiny - it is easier and more useful to deal with them in relative units
What type of atom does alpha decay occur in?
- Alpha decay occurs in very big atoms
- Which emit alpha particles from their nuclei to keep them stable
What is the nucleon and proton number of an alpha particle?
Nucleon number: 4
Proton number: 2
What happens to an atom after alpha decay?
Nucleon number decreases by 4
Proton number decreases by 2
State one trait of alpha particles
They are short range and can only travel a few centimetres in the air
Explain what happens in beta-minus decay
A neutron turns into a proton, emitting one beta-minus particle and electron antineutrino in the process
Why is an electron antineutrino emitted?
To conserve lepton number
Explain what happens in beta-plus decay
A proton turns into a neutron, emitting a positron (beta+ particle) and electron neutrino in the process
What force causes beta minus decay? What is its exchange particle?
The weak force
Exchange particle = W- boson
