Quantum Flashcards
Why is the strong force both attractive and repulsive?
To prevent the nucleus from collapsing or exploding
When is the strong force attractive?
> 0.5 fm
When is the strong force repulsive?
< 0.5 fm
What is the force responsible for beta decay?
the weak force
How strong is the weak force? (relative)
1 millionth of the strong force
How does the range of the weak force compare to that of the strong force?
It has a smaller range
What does the weak force act on?
Leptons and hadrons
What are the types of beta decay?
β+ and β-
When does beta decay occur?
When the nucleus emits an electron or a positron
What does a free neutron decay into in beta decay?
A proton, an electron and an anti-neutrino
What does a free proton decay into in beta plus decay?
A neutron, a positron and a neutrino
What type of beta decay is it when a free neutron decays into a proton?
β-
What type of beta decay is it when a free proton decays into a neutron?
β+
Why it called β- decay when a neutron decays into a proton?
An electron is produced
Why is it called β+ decay when a proton decays into a neutron?
A positron is produced
What happens to the unaccounted-for energy in beta decay?
It is carried away by the neutrinos
What happens if the nucleus is still unstable after emitting alpha or beta radiation?
It is in an excited state, and gives off gamma radiation
What does the strong force overcome?
The electrostatic forces of repulsion between protons in the nucleus
What type of particle are neutrinos?
Leptons
When are electromagnetic waves emitted?
When a charged particle loses energy
In what form is electromagnetic radiation emitted?
Photons - bursts or packets of energy
How do photons travel?
In one direction only in a straight line
What is one electron volt defined as?
The energy transferred when an electron is moved through a p.d. of 1V
What will happen if a particle-antiparticle pair meet?
They will annhiliate each other, their mass is converted into two gamma ray photons