Sam Ellis Particles

Question 1

Most of an atom is ______

Answer 1

Empty Space.

Question 2

the Proton number is also known as the

Answer 2

ATOMIC NOº / Z Number

Question 3

The mass number is also known as

Answer 3

Total number of protons and neutrons

Question 4

Define specific charge

Answer 4

Charge to mass ratio (Charge in C / Mass in KG)

Question 5

What makes something an isotope? (structure)

Answer 5

The same atomic number but different mass number (same protons different neutrons)

Question 6

Compare carbon-12 and carbon-13’s chemical properties.

Answer 6

Isotopes have = chemical properties but BIG changes in stability.

Question 7

What do we mean by isotopic data?

Answer 7

The amount of different isotopes in a substance.

Question 8

What are the 3 forces acting on nucleons?

Answer 8

EM Force

Gravity

STRONG NUCLEAR FORCE

Question 9

At what range is the strong nuclear force attractive?

Answer 9

0.5 - 3 fM

Question 10

What is a femto-meter?

Answer 10

1 x 10-15m

Question 11

How does the strong nuclear force act on different nucleons?

Answer 11

THE SAME for P-P N-P N-N

Question 12

What’s a use of isotopic data?

Answer 12

Carbon dating using carbon 13 abundance.

Question 13

Unstable nucli ______

Answer 13

Give off particles to stablise themselves

Question 14

Beta decay happens in _____ Nucli

Answer 14

Smaller

Question 15

alpha decay happens in _____ Nucli

Answer 15

larger

Question 16

Write a generic equation showing B- decay.

Answer 16

N -> P + E- + (ANTI ELECTRON NEUTRINO)

Question 17

Why was the neutrino hypothesised?

Answer 17

Just an electron doesn’t conserve momentum or energy or lepton number

Question 18

A Photon is

Answer 18

A discrete packet of energy

Question 19

What’s the equation that links frequency and energy

Answer 19

E=hf

energy = E =joules
Planks Constant = h = Constant
frequency = f = Hz

Question 20

Anti particles have the same ___ But opposing ____

Answer 20

Same = mass

opposing = charge baryon number and lepton number

Question 21

What is pair production?

Answer 21

When one photon of at least the rest mass (energy) of an antiparticle particle pair spontaneously becomes that p/ap pair.

Question 22

Why do we often pair produce e- and e+ pairs?

Answer 22

Electrons have a low rest energy (mass)

Question 23

Whats annihilation? and how much energy does the product have?

Answer 23

2 Particles (anti particle and particle pair) collide producing 2 photons of equal energy. The energy of the photons produced is (the rest mass + the total Ke)

Question 24

What’s PET? (positron emission spectroscopy)

Answer 24

We pass a positron emmiting source into the blood
We then look for an increase in photons from annihilation
this is detected by a scintilator.

Question 25

What does the strong nuclear force effect?

Answer 25

Hadrons only (mesons and baryons)

Question 26

What is the only stable nucleon?

Answer 26

a FREE proton

Question 27

All baryons eventually decay to ____

Answer 27

Protons.

Question 28

In strong interactions _____ is always conserved

Answer 28

STRANGNESS

Question 29

What is the exchange particle of the strong force

Answer 29

The pion.

Question 30

Which is heavier Kº or πº?

Answer 30

Kº - decays to pions via weak nuclear force.

Question 31

In the weak nuclear interaction ____ is not conserved

Answer 31

Strangeness.

Question 32

mesons interact with _____ via the _____

Answer 32

Baryons --- strong nuclear force.

Question 33

What are the 4 fundamental forces and what are their exchange particles?

Answer 33

Gravity - Graviton Strong Nu - Pion Weak Nu - W-/W+ EM - γ virtual photon.

Question 34

π vs k

Answer 34

Kaon is strange.

Question 35

Leptons are ____ Particles

Answer 35

Fundamental

Question 36

Leptons interact via ____, _____ and _____ not _____

Answer 36

Weak Em Gravity NOT STRONG - They're fundamental.

Question 37

What is a muon?

Answer 37

A Heavy electron that will decay to form an electron.

Question 38

What gives rise to strange particles?

Answer 38

The strong nuclear force only.

Question 39

What is the strangeness of Kº K+ and K-

Answer 39

Kº = +/- 1 K+ = 1 K- = -1

Question 40

Mesons are made up from _____

Answer 40

quark anti quark pair

Question 41

Explain quark confinement.

Answer 41

The idea that quarks cannot exist by themselves. They can only exist as a hadron. If you put energy into remove a U you keep going until you end up forming a U aU pair.

Question 42

Weak interaction can ______ Quarks

Answer 42

Change the character (U --> D for eg)

Question 43

a W+ boson has _____ of a proton this explains _____

Answer 43

100x the mass. The short range of the weak force.

Question 44

What's the range of the electrostatic force? why?

Answer 44

INFINITE. (photon has no mass so can travel infinite amounts)

Question 45

define electron volt

Answer 45

the work done on an electron in accelerating it through a potential difference of one volt.