(Particle Physics) A Level Physics Topic 1

What are the three types of subatomic particles that make up an atom: Electrons, Protons, Neutrons

What makes up the central core of the atom: Protons and Neutrons

Which of the following particles orbit around the nucleus of an atom: Electrons

What is most of an atom made up of: Empty space

What does the Proton number (Z) represent: The number of protons in the nucleus

What does the Nucleon number (A) represent: The total number of protons and neutrons

What are atoms of the same element with different nucleon numbers called: Isotopes

What is the same in each isotope of an element: Number of protons

What varies in each isotope of an element: Number of neutrons

Protons and neutrons make up the central core of an atom called the: Nucleus

What is specific charge: The ratio of charge to mass

What is the unit of specific charge: Coulombs per kilogram (C/kg)

How is the charge of a gold nucleus calculated: Atomic number x charge of proton

Specific charge of neutral atom: Zero

How is the charge of a lithium ion calculated: Mass number x elementary charge

How is the mass of a gold nucleus calculated: Mass number x atomic mass unit

Explain the steps to calculate the specific charge of a gold nucleus: Determine the charge and mass of the Gold nucleus and then calculate the specific charge

Why is the specific charge of atoms zero: Because the number of positive protons in the nucleus is balanced by the number of negative electrons

What force causes protons to repel each other within the atomic nucleus: Electromagnetic force

What force holds the protons and neutrons together within the atomic nucleus: Strong nuclear force

At what distance does the strong nuclear force become repulsive between nucleons: Less than 0.5 fm

Which particles does the strong nuclear force act on: Both protons and neutrons

What determines if an atomic nucleus will be stable or unstable: Strength of the strong nuclear force

What is the name given to the particles inside the atomic nucleus: Nucleons ( Protons and Neutrons)

Briefly explain why both the strong nuclear force and electromagnetic force are important within the atomic nucleus: The strong nuclear force holds protons and neutrons together in the nucleus and the electromagnetic force caused protons to repel each other because they have the same positive charge

Give three properties of the strong nuclear force: Acts over a short range up to about 3 fm. Attractive between 0.5 and 3 fm, but repulsive below 0.5 fm. Much stronger than the eletromagnetic force

How does the atomic number change during alpha decay: Decreases by 2

What are the changes to the nucleus during beta minus decay: Proton number increases and the nucleon number stays the same

What particle is emitted along with the positron during beta plus decay: A neutrino

Briefly explain the key changes to the nucleus during alpha decay: Loses 2 protons and 2 neutrons. The atomic number decreases by 2. The mass number decreases by 4

What does Photon’s energy depend on: Its frequency and is related to Planck’s constant

What is discrete bundle of electromagnetic energy called: A photon

Give three examples of electromagnetic radiation: Radiowaves, Microwaves, X-Rays

Which particle has a positron as its antiparticle: Electron

What charge does an antiparticle have compared to its normal particle counterpart: The opposite charge

Neutron particle to its antiparticle: Anti neutron

Proton particle to its antiparticle: Anti proton

Electron particle to its antiparticle: Positron

In pair production, what must the minimum photon energy be equal to: The rest energy of the particles produced

In annihilation, what form does the mass-energy of the particle and antiparticle convert into: Two Photons

What must be true about the total energy of the photons produced in annihilation: It must equal twice the rest energy of the particle

What is the process where energy is converted into a particle and antiparticle pair called: Pair production

What consists of antiparticles rather than normal particles: Antimatter

Explain the process of electron-positron annihilation: An electron and a positron are oppositely charged. When they meet they destroy each other. Their mass turns into energy, releasing two gamma photosn. These photons go in opposite directions to conserve momentum.

Two types of hadrons: Baryons and Mesons

Baryon number of Baryon: +1

What is the baryon number of the antiproton: -1

Which particle has a baryon number of 0: Electron

Which lepton has a charge of -1: Muon

Which conservation law requires lepton number on the left = lepton number on the right: Lepton number conservation

What are particles made up of quarks called: Hadrons

List 3 leptons and their charges: Electron -1, muon -1 and tau -1

What is the baryon number of the down quark: + 1/3

Which meson contains an up quark and an anti-down quark: n+

What are particles comprised of three quarks called: Baryons

What name is given to the antiparticle counterparts of quarks: Antiquarks

What is the quark composition of a proton: 2 up quarks and 1 down quarks

What is the quark composition of the neutron: 1 up quarks and 2 down quarks

What interaction allows the strangeness number to change: Weak

What has a strangeness number of -1: Strange quark