Particles And Radiation 19-46

Question 1

What’s a nucleon?

Answer 1

Protons and neutrons

Question 2

How is specific charge calculated?

Answer 2

Specific charge = Charge / Mass

Question 3

What is specific charge?

Answer 3

The charge to mass ratio of a particle

Question 4

What’s an isotope?

Answer 4

An atom with the same number of protons but a different number of neutrons

Question 5

How does the strong nuclear force keep nuclei stable?

Answer 5

By counteracting the electrostatic force of repulsion between protons in the nucleus (as they have the same charge)

Question 6

When is the SNF repulsive?

Answer 6

0-0.5 fm

Question 7

When is the SNF attractive?

Answer 7

Between 0.5-3 fm

Question 8

What happens to the strong nuclear force after 3 fm?

Answer 8

It is not attractive or repulsive

Question 9

Why do nuclei decay?

Answer 9

When it has too many protons, neutrons or both which causes SNF to not be enough to keep them stable, therefore these nuclei will decay in order to become stable

Question 10

When does alpha decay occur?

Answer 10

Large nuclei with too many protons and neutrons

Question 11

What happens in alpha decay?

Answer 11

An alpha particle (helium nucleus) is produced and the particle decays accordingly

Question 12

When does beta-minus decay occur?

Answer 12

Nuclei which are neutron-rich (have too many neutrons)

Question 13

What happens in beta-minus decay?

Answer 13

A beta particle (electron) is produced along with an anti neutrino and the particle decays accordingly

Question 14

What’s the antiparticle of an electron and neutrino?

Answer 14

The positron and the anti neutrino

Question 15

What’s a photon?

Answer 15

Electromagnetic radiation that travels in pockets

Question 16

What’s annihilation?

Answer 16

Where a particle and its corresponding antiparticle collide

Question 17

What happens in annihilation?

Answer 17

The particles’ masses are converted into energy, this energy, along with the kinetic energy of the two particles is released in the form of 2 photons moving in opposite directions in order to conserve momentum.

Question 18

Whats pair production?

Answer 18

Where protons collide or a photon is converted into an equal amount of matter and antimatter

Question 19

When does pair production occur?

Answer 19

When the photon has an energy greater than the total rest energy of both particles, any excess energy is converted into kinetic energy of the particles

Question 20

What are the 4 fundamental forces?

Answer 20

Gravity, electromagnetic, weak nuclear and strong nuclear

Question 21

How do these forces occur?

Answer 21

Exchange particles​ carry energy and momentum between the particles experiencing the force and each fundamental force has its own exchange particles

Question 22

Name the exchange particle and what it acts on: SNF

Answer 22

Gluon, hadrons

Question 23

Name the exchange particle and what it acts on: WNF

Answer 23

W boson ( W + or W − ), all particles

Question 24

Name the exchange particle and what it acts on: Electromagnetic force

Answer 24

Virtual photon ( γ ), charged particles

Question 25

What force is responsible for beta decay?

Answer 25

WNF

Question 26

What’s the equation for Electron capture?

Answer 26

Proton + electron → neutron + electron neutrino (W+ boson)

Question 27

What’s the equation for electron-proton collision?

Answer 27

Proton + electron → neutron + electron neutrino (W- boson)

Question 28

What’s the equation for beta-plus decay?

Answer 28

Proton → neutron + positron + electron neutrino (W+ boson)

Question 29

What’s the equation for beta-minus decay?

Answer 29

Neutron → proton + electron + electron anti neutrino (W- boson)

Question 30

What are the 2 classes of particles?

Answer 30

Hadrons or leptons

Question 31

What is different between leptons and hadrons?

Answer 31

Leptons are fundamental particles, meaning they can’t be broken down any further and don’t feel the SNF, however hadrons are formed of quarks (fundamental) and experience the SNF

Question 32

What can hadrons be separated into?

Answer 32

Baryons, anti baryons and mesons

Question 33

What is a baryons / anti baryons formed of?

Answer 33

3 quarks / 3 antiquarks

Question 34

What are mesons formed of?

Answer 34

A quark and an antiquark

Question 35

What’s the only stable baryon?

Answer 35

Protons, therefore all other baryons will decay into a proton eventually

Question 36

What does a muon decay into?

Answer 36

An electron

Question 37

What are strange particles?

Answer 37

Particles which are ​produced by the strong nuclear interaction but decay by the weak interaction​

Question 38

Give an example of a strange particle and what it decays into

Answer 38

Kaons which decay into pions through the weak interaction

Question 39

What’s strangeness?

Answer 39

A property of particles, which shows that strange particles must be created in pairs, as strangeness must be conserved in strong interactions

Question 40

What’s the baryon number of the up, down and strange quark?

Answer 40

+ 1/3

Question 41

What’s the charge of the up, down and strange quark?

Answer 41

+ 2/3, - 1/3, - 1/3

Question 42

What the equation for neutron decay?

Answer 42

Neutron → proton + electron + electron antineutrino

Question 43

What’s things must always be conserved in a particle interaction?

Answer 43

● Energy and momentum
● Charge
● Baryon number
● Electron lepton number
● Muon lepton number