Section 1: Particles & Radiation

Question 1

What is the realtionship between specific charge and mass?

Answer 1

specific charge is inversly proprtional to mass

Question 2

How do you find specific charge?

Answer 2

Charge/ mass

Question 3

What is meant by spesific charge of a particle? untis?

Answer 3

the ratio of its charge to mass (C kg-1)

Question 4

describle how the strong nuclear force varies with the spereation of neuclons.

Answer 4

• repulsive then attractive
  -short range (0.5- 2.5) fm ish
• cross to atractive around 0.7 fm
  -prevents protons and neutrons from moving closer or further apart

Question 5

What neucles is the same as a alpha particle?

Answer 5

helium neucleus

Question 6

What is the neuclon number?

Answer 6

number of protons and neurons, mass number

Question 7

What guage boson is used in strong interaction? and what particles are effected?

Answer 7

guage boson - pion (0+-)
particles - hadrons

Question 8

What guage boson is used in electromagnetic interaction? and what particles are effected?

Answer 8

virtual photon
only charged particles

Question 9

What guage boson is used in weak interaction? and what particles are effected?

Answer 9

w+ w- bosons
all types of particles are effected

Question 10

What is the equation for beta minus decay? and what is the guage boson present?

Answer 10

n—> p + electron + anti-neutrino. W-

Question 11

What is the equation for beta plus decay? and why is the guage bosson present?

Answer 11

P—> n + (e+) + neutrino W+

Question 12

What is the equation for electron capture? and what is the guage bosson present?

Answer 12

P + e- —> n + netrino W+

Question 13

What is the equation for electron proton collision? What is the guage bosson present (why)?

Answer 13

Same as electron capture
P + (e-) —> n + neutrino
W- bosson because:
-comes from the electron
- W- to conserve charge

Question 14

What do kaons decay into?

Answer 14

Pions

Question 15

How do you find the minimum energy for anhilation?

Answer 15

min energy of EACH photon = rest mass

Question 16

How do you find the minimum energy for pair production?

Answer 16

min energy of photon = 2x rest mass of the particle made

Question 17

How does a K- particle decay?

Answer 17

k- —> Pion 0 + (e-) + anti neutrino

Question 18

Explain what is meant by electron capture?

Answer 18

• an orbital/shell electron
• interacts with a proton in the neuclus
• via the weak interaction

Question 19

State what roles exchange particles can play in an interaction.

Answer 19

• transfer energy
  -transfer momentum
  -transfer force
  (somtimes) transfers charge

Question 20

What is an electrons lepton numbers and charge?

Answer 20

Le +1 lu 0 charge -1

Question 21

What is an electron neutrino lepton numbers and charge?

Answer 21

Le +1 lu 0 charge 0

Question 22

What is an muons’ lepton numbers and charge?

Answer 22

Le 0 lu +1 charge -1

Question 23

What is a muon neutrino lepton numbers and charge?

Answer 23

Le 0 Lu+1 charge 0

Question 24

What patricle is the only stable baryon?

Answer 24

proton

Question 25

What are caracterisitcs of a strange particle that makes it diffrent to particles that are not strange?

Answer 25

- contains a strange quark - longer half life than expected -decays by the weak interaction

Question 26

What is annhilation?

Answer 26

The process of a particle and its antiparticle colliding and being converted into energy. The energy is released in two photons to conserve momentum.

Question 27

What are the products of pair production?

Answer 27

Two protons fired together - A proton anti proton pair. A gamma photon -An electron positron pair

Question 28

What interaction is present for the dacay of strange particles? Is strangeness conseverd?

Answer 28

Weak interaction Not always conserved

Question 29

In what sized atom does alpha decay usually happen?

Answer 29

In atoms with more than 82 protons

Question 30

Antiparticle:​

Answer 30

All particles have a corresponding antiparticle with the same mass but opposite charge and conservation numbers.

Question 31

What do muons deacy into?

Answer 31

Electrons

Question 32

Stopping Potential:​

Answer 32

The minimum potential difference required to stop the highest kinetic energy electrons from leaving the metal plate in the photoelectric effect.

Question 33

Threshold Frequency: ​

Answer 33

The minimum frequency of photons required for photoelectrons to be emitted from the surface of a metal plate through the photoelectric effect. It is equal to the metal’s work function divided by Planck’s constant.

Question 34

Work Function: ​

Answer 34

The minimum energy required to remove an electron from a metal’s surface.