standard Model

Question 1

What force is carried by a photon?

Answer 1

Electromagnetic Force

Question 2

Give an example of a Baryon.

Answer 2

Proton

Neutron

Question 3

What is meant by a Meson?

Answer 3

Mesons are made from 2 quarks.

They always consist of a quark and an antiquark pair.

Question 4

What is a Boson?

Answer 4

Bosons are force carrying particles.

Question 5

What is beta (minus) decay?

Answer 5

Beta (minus) decay is when a neutron decays into a proton releasing an electron and an antineutrino.

Question 6

Name the four Bosons.

Answer 6

1. Photons
2. W and Z Bosons
3. Gluons
4. Gravitons

Question 7

What is meant by a Hadron?

Answer 7

Particles made from quarks

Question 8

What is the Standard Model?

Answer 8

The Standard Model explains how the basic building blocks of matter interact, governed by four fundamental forces.

Question 9

What is a fundamental particle?

Answer 9

A fundamental particle is one that cannot be broken down into any sub particles.

Question 10

What did beta decay provide the first evidence for?

Answer 10

The existence of neutrinos.

Question 11

Why were neutrinos suggested as an extra particle produced as a result of beta decay?

Answer 11

When beta decay occurs momentum and energy should be conserved. This was not happening if only the proton and beta particle were considered. There had to be another particle that carried the rest of the energy away.

Question 12

What evidence is there for antimatter?

Answer 12

Positrons discovered ocurring naturally in cosmic rays.

Question 13

What force is carried by a Graviton?

Answer 13

Gravity force

Question 14

How does an antimatter particle compare with a matter particle?

Answer 14

Antimatter particle has similar properties to the matter particle but equal and opposite charge.

Question 15

What can you say about electrons absorbing photons in the photoelectric effect?

Answer 15

• An electron can only absorb the energy from one photon
• The electron absorbs all the energy from the photon.

Question 16

Why does the photoelectric effect give evidence for light to be considered as a particle?

Answer 16

• Photoelectric effect cannot be explained if light is thought of as a wave or any light would cause photoemission if it shone on the surface long enough to deliver enough energy to the electrons..
• Each photon contains a discrete amount of energy which results in one photon ejecting one electron

Question 17

What is meant by a Baryon?

Answer 17

Baryons are made from 3 quarks

Question 18

What force is carried by a Gluon?

Answer 18

Strong force

Question 19

If an incident photon is greater than the work function what happens to the rest of the photon’s energy?

Answer 19

The electron that is ejected has the rest of the energy as kinetic energy.

Question 20

If an unstable nucleus undergoes beta decay what is given out and what is the effect on the mass number and the atomic number?

Answer 20

An electron from the nucleus is given out along with an antineutrino.

The mass number of the product remains the same and the atomic number increases by one.

Question 21

What will a stationary charge create?

Answer 21

An electric field

Question 22

What is the Work Function?

Answer 22

The minimum energy required to eject an electron from a metal surface.

Question 23

What are the two types of Fermions?

Answer 23

Quark

and

Lepton

Question 24

What will a moving charge create?

Answer 24

1. An electric field
2. Magnetic field

Question 25

Describe the field lines between two negative charges.

Answer 25

The field lines run towards the negative charges but no filed lines between them.

Question 26

In the photoelectric effect, what happens to the maximum kinetic energy of an electron if the irradiance is increased? Why?

Answer 26

* There is no effect on the maximum kinetic energy it remains the same. * The energy of the incident photons (E = hf) is unchanged.

Question 27

What force is carried by W and Z bosons?

Answer 27

Weak force

Question 28

If an unstable nucleus undergoes alpha decay what is given out and what is the effect on the mass number and the atomic number?

Answer 28

An alpha particle is a helium nucleus. **Mass Number -** This means that the product mass number + the mass number of a helium nucleus = mass number of the original unstable nucleus. **Atomic Number** - This means that the product atomic number + the atomic number of a helium nucleus = atomic number of the original unstable nucleus.

Question 29

What is the effect of an electric field on a charged particle?

Answer 29

The particle will experience a force that causes an acceleration.

Question 30

Describe the electric field around a negative charge.

Answer 30

Field lines towards negatively charged particle.

Question 31

What are the names of the 6 types of **Quarks**?

Answer 31

1. Up 2. Down 3. Charm 4. Strange 5. Top 6. Bottom

Question 32

A proton is made up of two up quarks and a down quark. The up quarks are both positively charged. Why does the proton not get torn apart?

Answer 32

Gluons carry the strong force to hold the quarks together. This strong force is greater than the force of repulsion between the particles.

Question 33

What is a **Fermion**?

Answer 33

It is a matter particle.

Question 34

What are the names of the 6 types of **Leptons**?

Answer 34

1. Electron 2. Electron neutrino 3. Muon 4. Muon neutrino 5. Tau 6. Tau Neutrino