Topic 8: Nuclear and Particle Physics: Part Two

Question 1

What is the difference between matter particles and antimatter particles?

Answer 1

They have the opposite electric charge of each other.

Question 2

What two things matter particles and their antimatter counterpart have in common

Answer 2

Identical mass and rest mass energy.

Question 3

What is always conserved when particle interaction equation?

Answer 3

Quantum numbers.

Question 4

What quantum numbers are conserved in particle interaction?

Answer 4

Charge (Q), baryon number (B), and lepton number (L).

Question 5

What has a charge Q = +1 in particle interactions?

Answer 5

Protons and positrons.

Question 6

What has a charge Q = -1 in particle interactions?

Answer 6

Electrons + other leptons.

Question 7

What is the baryon number?

Answer 7

The number of baryons in an interaction.

Question 8

What has a baryon number B = +1 in a particle interaction?

Answer 8

Baryons like protons and neutrons.

Question 9

What has a baryon number B = -1 in a particle interaction?

Answer 9

Anti-baryons.

Question 10

What has a baryon number B = 0 in a particle interaction?

Answer 10

Anything that is not a baryon, e.g. leptons and mesons.

Question 11

What has a baryon number B = +1/3 in a particle interaction?

Answer 11

Quarks.

Question 12

What has a baryon number B = -1/3 in a particle interaction?

Answer 12

Anti-quarks.

Question 13

Why are baryons made up of only all quarks or anti-quarks, not a mixture?

Answer 13

So, the baryon number adds up to an integer. A mixture would not produce an integer baryon number.

Question 14

What are baryons made up of?

Answer 14

Only quarks.

Question 15

What are anti-baryons made up of?

Answer 15

Only anti-quarks.

Question 16

What is the lepton number?

Answer 16

The number of leptons in an interaction.

Question 17

What has a lepton number L = +1 in a particle interaction?

Answer 17

Leptons like electrons and neutrinos.

Question 18

What has a lepton number L = -1 in a particle interaction?

Answer 18

Anti-leptons.

Question 19

What has a lepton number L = 0 in a particle interaction?

Answer 19

Not leptons.

Question 20

What things must be conserved for a possible particle interaction (conservation laws)?

Answer 20

Charge, baryon number, lepton number, energy(or mass-energy) and momentum.

Question 21

What happens if the conservation laws for particle interactions are not met?

Answer 21

The interaction is impossible/cannot occur.

Question 22

What values can Q, B and L numbers can take?

Answer 22

Discrete values.

Question 23

What to do to check if a particle interaction is possible?

Answer 23

Check if each quantum number is equal on both sides of the equation. If one of them is not equal, then the interaction cannot occur.

Question 24

What are the 4 gauge bosons?

Answer 24

• Bosons
• Virtual photons
• Gluons
• Gravitons

Question 25

What is the symbol for virtual photons?

Answer 25

γ

Question 26

What is the symbol for gluons?

Answer 26

g

Question 27

What is the symbol for bosons?

Answer 27

W⁺, W⁻ and Z⁰

Question 28

What are the 4 fundamental forces?

Answer 28

1. Gravitational forces 2. Electromagnetic forces 3. Weak nuclear forces 4. Strong nuclear forces

Question 29

What are the fundamental forces carried by?

Answer 29

Gauge bosons.

Question 30

What particles experience gravitational force?

Answer 30

All particles with mass

Question 31

What is the range of gravitational force?

Answer 31

Infinite.

Question 32

What gauge boson is gravitational force carried by?

Answer 32

G, gravitons. [hypothetically]

Question 33

What particles experience weak nuclear force?

Answer 33

Quarks and leptons

Question 34

What is the range of weak nuclear force?

Answer 34

Very short, 10⁻¹⁷ m.

Question 35

What gauge boson is weak nuclear force carried by?

Answer 35

W⁺, W⁻ and Z⁰ bosons

Question 36

When is weak nuclear force significant?

Answer 36

When electromagnetic and strong nuclear interactions do not operate.

Question 37

What particles experience electromagnetic force?

Answer 37

All charged particles

Question 38

What is the range of electromagnetic force?

Answer 38

Infinite.

Question 39

What gauge boson is electromagnetic force carried by?

Answer 39

γ, virtual photons.

Question 40

What particles experience strong nuclear force?

Answer 40

Quarks and particles made of quarks.

Question 41

What is the range of strong nuclear force?

Answer 41

Short, 10⁻¹⁵ m.

Question 42

What gauge boson is strong nuclear force carried by?

Answer 42

g, gluons.

Question 43

What is the symbol for an up quark?

Answer 43

u

Question 44

What is the symbol for a down quark?

Answer 44

d

Question 45

What is the symbol for a charm quark?

Answer 45

c

Question 46

What is the symbol for a strange quark?

Answer 46

s

Question 47

What is the symbol for a top quark?

Answer 47

t

Question 49

What is the symbol for a bottom quark?

Answer 49

b

Question 50

What is the symbol for an anti-quark?

Answer 50

Its normal quark symbol with a bar on the top.

Question 51

What does the symbol “u” represent?

Answer 51

A up quark.

Question 52

What does the symbol “d” represent?

Answer 52

A down quark.

Question 52

What does the symbol “c” represent?

Answer 52

A charm quark.

Question 53

What does the symbol “s” represent?

Answer 53

A strange quark.

Question 54

What does the symbol “t” represent?

Answer 54

A top quark.

Question 55

What does the symbol “b” represent?

Answer 55

A bottom quark.

Question 56

What is the charge for an up quark?

Answer 56

+⅔e

Question 57

What is the charge for a down quark?

Answer 57

-⅓e

Question 58

What is the charge for a charm quark?

Answer 58

+⅔e

Question 59

What is the charge for a strange quark?

Answer 59

-⅓e

Question 60

What is the charge for a top quark?

Answer 60

+⅔e

Question 61

What is the charge for a bottom quark?

Answer 61

-⅓e

Question 62

What is the charge for an anti-quark?

Answer 62

Multiply the original quark’s charge by -1.

Question 63

What is the symbol for an electron?

Answer 63

e-

Question 64

What is the symbol for a muon?

Answer 64

μ-

Question 65

What is the symbol for a tau?

Answer 65

τ-

Question 66

What is the symbol for an electron neutrino?

Answer 66

𝒱e

Question 67

What is the symbol for a muon neutrino?

Answer 67

𝒱μ

Question 68

What is the symbol for a tau neutrino?

Answer 68

𝒱τ

Question 69

What is the charge of a lepton?

Answer 69

-1e

Question 70

What is the charge of neutrinos?

Answer 70

No charge.

Question 71

What is the relative charge of an electron?

Answer 71

-1

Question 72

What is the relative charge of a positron?

Answer 72

+1

Question 73

What is the relative charge of an anti-proton?

Answer 73

-1

Question 74

What is the relative charge of a neutron?

Answer 74

0

Question 75

What is the relative charge of an anti-neutron?

Answer 75

0

Question 76

What is the symbol for a positron?

Answer 76

e+

Question 77

What is the symbol for a proton?

Answer 77

p

Question 79

What is the symbol for a neutron?

Answer 79

n

Question 80

What does the symbol “e+” represent?

Answer 80

A positron.

Question 81

What does the symbol “p” represent?

Answer 81

A proton.

Question 81

What does the symbol “n” represent?

Answer 81

A neutron.

Question 82

What is the quark content of a proton?

Answer 82

uud

Question 83

What is the quark content of a neutron?

Answer 83

udd

Question 84

What is the quark content of a K⁺?

Answer 84

u s̅

Question 85

What is the quark content of a K⁰?

Answer 85

d s̅

Question 86

What is the quark content of a K⁻?

Answer 86

s u̅

Question 87

What is the quark content of a π⁺?

Answer 87

ud̅

Question 88

What is the quark content of a π⁰?

Answer 88

u u̅ or d d̅

Question 89

What is the quark content of a π⁻?

Answer 89

d u̅

Question 90

What is the quark content of a lambda particle (Λ⁰) ?

Answer 90

u d s

Question 91

Why are collisions high energy?

Answer 91

Energy required to overcome electrostatic repulsion. Since particles move fast the energy/momentum must be high, shorter de broglie wavelength.

Question 92

Why are only a low proportion of decays detected?

Answer 92

* emmisions in all directions * some emitted particles may be absorbed by the material in the sample * some emitted particles may be absorbed by the window * some pass through the detector

Question 93

What does firing electrons at a hydrogen target tell us?

Answer 93

* proton is not uniform, it has some empty space since some electrons passed through * made up of smaller particles called quarks

Question 94

What is the atomic process that produces emission spectra?

Answer 94

electron drops down energy levels and de-excites releasing energy