Unit 1.7: Particles and Nuclear Structure Flashcards
Matter is composed of atoms, but within atoms there are sub atomic particles. What are these sub atomic particles called?
Leptons and Quarks
, ;What are quarks?
Relatively high mass particles, are either ‘up’ or ‘down’. These particles are affected by the strong force
What are leptons?
Leptons are lightweight particles and have two types. These are affected by the weak force
What are the two types of leptons?
Electron and electron neutrino
For each particle, there exists an ‘antiparticle’. What is meant by the term antiparticle?
Antiparticles have the same mass but opposite charge to their counterpart.
Do quarks exist in groups or in isolation?
In groups
When quarks are in a group of 3, what is the group called?
Baryons
How many possible ways to combine up and down quarks can form a baryon?
4
State the possible combinations to form a baryon?
uud, udd, uuu, ddd
What is the baryon uud known as?
Proton,p
What is the charge of a proton?
+1
What is the baryon udd known as?
neutron,n
What is the charge of a neutron?
0
What is the baryon uuu known as?
delta plus plus,Δ++
What is the charge of a delta plus plus?
+2
What is the baryon ddd known as?
delta minus,Δ-
What is the charge of a delta minus?
-1
There is an excited version of the uud and udd baryons, what are they also classed as?
Delta particles
What is the delta particle of an excited proton?
Δ+
What is the delta particle of an excited neutron?
Δ0
How are antiparticles represented?
A small bar above the symbol
Quarks can also form in pairs, what are these pairs called?
Mesons
How many types of mesons are there?
4
Mesons must either be a quark or an ___?
Anti-quark
For 1st generation particles, what are these mesons known as?
Pions or pi messons
List the 4 combinations of a meson
udˉ,uˉd, uuˉ,ddˉ
What is the name given to the meson uˉd and state its charge
Name:pi minus,
Symbol: π −
Charge: -1
What is the name given to the meson udˉ and state its charge ?
Name: pi plus
Symbol: π +
Charge: =1
What is the name given to the mesons, uuˉ and ddˉ and state their charge
Name: Pi zero
Symbol: π 0
Charge: 0
State the conservation of momentum in terms of particles.
In any interaction between particles in a system, the total momentum must stay constant
State the conservation of energy in terms of particles
In any interaction between particles in a system, mass/energy must neither be created or destroyed
State the conservation of charge
In any interaction between particles in a system, the total charge in the system must not change.
State the conservation of baryon number.
In any interaction between particles in a system, the total baryon number in the system must not change.
State the conservation of lepton number
In any interaction between particles in a system, the total lepton number in the system must not change
There are 4 fundamental forces involved in interactions between particles. State them
Gravitational, strong force, weak force and the electromagnetic force
Gravitational forces are experienced by___
All matter
Weak forces are experienced by____
All leptons and all quarks
What is the range for gravitational forces?
Infinite
What is the range for weak forces?
very short
What is the range for electromagnetic forces?
infinite
What is the range for strong forces?
short
EM forces are experienced by ___
All charged particles
All strong forces are experienced by__
All quarks.
