Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2.Particles - A level Physics > 2.2 - Classification of Particles > Flashcards

2.2 - Classification of Particles Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What are hadrons?

A

The group of subatomic particles that are made up of quarks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What force do hadrons feel?

A

The strong nuclear force.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 2 classes of hadrons?

A

Baryons
Mesons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are baryons?

A

Particles made of 3 quarks (like protons and neutrons.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are mesons?

A

Particles made of a quark and anti-quark pair (like pions and kaons).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are anti-baryons?

A

Anti-particles made of 3 anti-quarks (like anti-protons and anti-neutrons).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are anti-mesons?

A

Anti-particles made of a quark and anti-quark pair (like anti-pions and anti-kaons).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a rule with quark combinations?

A
  • only found in pairs of 3 quarks or 3 antiquarks.
  • or found as a quark anti-quark pair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the baryon number?

A

The number of baryons in an interaction.
It must be conserved in all interactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the baryon numbers of different particles?

A

Baryons = +1
Anti-baryons = -1
Particles that aren’t baryons = 0
(baryon number must always be an integer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 3 types of quark?

A

up (u)
down (d)
strange (s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the only stable baryon and why?

A

The proton because it has the longest half-life and is the lightest baryon.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What particle do all baryons eventually decay into?

A

The proton.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the lightest meson?

A

The pion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is particle exchange?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an exchange particle?

A

A virtual particle that mediates (bring about) the interaction between two other particles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are pions responsible for?

A

Binding nucleons together. (AKA the strong nuclear force).
Used as an exchange particle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How are kaons produced?

A

By the strong interaction between pions and protons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What do kaons decay into?

A

Pions.

20
Q

Why do kaons have unusually long lifetimes?

A

They contain a strange quark.

21
Q

What force do kaons decay through?

A

The weak interaction.

22
Q

What are leptons?

A

A group of fundamental particles that aren’t made up of any other particles (like quarks).

23
Q

What force do leptons interact with?

A

Weak, gravitational or electromagnetic.

24
Q

What are the most common leptons?

A
  • The electron
  • The electron neutrino
  • The muon
  • The muon neutrino
25
Q

What is heavier, the electron or the muon?

A

The muon.

26
Q

Why aren’t quarks classed as leptons?

A

Leptons do not interact with the strong force whilst quarks do.

27
Q

What is the lepton number of different particles? (L)

A

Leptons = +1
Anti-leptons = -1
Particles that aren’t leptons = 0

28
Q

What do muons decay into?

A

Electrons.

29
Q

What force does muon decay occur through?

A

The weak interaction.

30
Q

What is the exchange particle of muon decay?

A

W⁻ boson.

31
Q

Which group of particles are made of quarks?

A

All hadrons.

32
Q

What are the 3 anti-quarks?

A

Anti-up
Anti-down
Anti-strange

33
Q

What is the strangeness of all quarks and anti-quarks?

A

Up, down, anti-up and anti-down = 0
Strange = -1
Anti-strange = +1

34
Q

What is the quark composition of a proton?

A

up, up, down
uud.

35
Q

What is the quark composition of a neutron?

A

up, down, down
udd.

36
Q

What is the quark composition of a π⁺?

A

up, anti-down.
u /d

37
Q

What is the quark composition of a π⁻?

A

Anti up, down.
/u d

38
Q

What is the quark composition of a π⁰?

A

up, anti-up
OR
down, anti-down
u /u
d /d

39
Q

What is the quark composition of a K⁺?

A

up, anti-strange
u /s

40
Q

What type of quark do all kaons have?

A

A strange or anti strange quark.

41
Q

What is the quark composition of a K⁻?

A

anti-up, strange
/u s

42
Q

What is the quark composition of a K⁰?

A

Anti-down, strange
OR
down, anti-strange
/d s
d /s

43
Q

What are 3 properties of strange particles?

A
  • Produced through the strong interaction
  • Decay through the weak interaction
  • Produced in quark-antiquark pairs
44
Q

What is the exchange particle of the weak interaction?

A

W⁺ boson.
(eg - kaon decay)

45
Q

Where is strangeness not conserved?

A

Through the weak interaction.

46
Q

What are 2 reasons why particle accelerators used to collide particles at high speeds?

A
  • To produce new particles
  • Reveal the inner structure of particles

2.Particles - A level Physics (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions