Unit 1 - Particles And Radiation Flashcards
What is the quark structure of a baryon? (1)
Three quarks
What property defines a hadron? (1)
Particles that experience the strong force/interaction
What is the quark structure of a meson? (1)
Quark and antiquark
State one similarity and one difference between a particle and its antiparticle? (2)
Similarity - rest mass/energy
Difference - opposite charge
State the interaction, with a reason, responsible for the decay of a K- into a negative muon and antineutrino? (2)
Weak interaction
Because strange not conserved
What part of the atom is the same as a β- particle? (1)
Electron
What particle is difficult to detect from β+ decay? (1)
Neutrino
Give the quark structure of a neutron and proton (1)
Proton - uud
Neutron - ddu
Describe how the strong nuclear force between two nucleons varies with distance, stating suitable values of desperation (3)
- Repulsive then attractive
- Short range
- pre 0.4fm repulsive, after attractive
What is meant by isotopes (2)
- Same atomic number/proton number
* Different number of nucleons/neutrons
State one difference between hadrons and leptons (1)
Leptons do not experience strong interaction, hadrons do
Or
Hadrons not fundamental, leptons are
Hadrons can be divided into two groups. Name the groups and state a difference (3)
- Baryons
- Mesons
- Baryons three quarks, mesons quark and antiquark
Which constituent of an atom has the largest specific charge? (1)
Electron
Name two baryons (2)
Proton, neutron
State the quark structure of the pion π+ (1)
Up and antidown
Give one characteristic of a strange particle that makes it different from a particle that is not strange (1)
Contains strange quark Or Longer half life than expected Or Decays by weak interaction
State what is meant by isotopes (2)
- Same atomic number/ number of protons
* Different mass/ nucleon number/ number of neutrons
Explain why the alpha particle, once outside the nucleus, is unaffected by the strong nuclear force. (2)
- Strong nuclear force has short range
* No effect at distances larger than 3fm
Where does the electron in pair production come from? (1)
Inner shell of atom
State what is meant by specific charge and give an appropriate unit for this quantity. (2)
- The ratio of charge to mass
* Ckg^-1
State the quark composition of a meson. (1)
Quark antiquark pair
State the Baryon number of the K- meson. (1)
0
State the quark composition of the K- meson. (1)
Anti up and strange quark
What particle is responsible for the decay of a strange quark. (1)
Weak interaction
