AS unit 1
phya1
particles
quantum phenomena
electricity
GCE PHYSICS
AS Examination
Unit 1 . PHYA1 Particles, Quantum Phenomena and Electricity
Written Examination . 70 marks, 6 or 7 structured questions
1 ¼ hours
,40% of the total AS marks
20% of the total A-Level marks available June
Unit 2 . PHYA2 Mechanics, Materials and Waves
Written Examination . 70 marks, 6 or 7 structured questions
1 ¼ hours
40% of the total AS marks
20% of the total A-Level marks available June
Unit 3 Investigative and Practical Skills in AS Physics
PHA3X, Externally Marked Route X . 55 marks
Practical Skills Verification (PSV . teacher verification)
Externally Marked Practical Assignment (EMPA . 55 marks)
20% of the total AS marks
10% of the total A-Level marks available June only
A2 Examination
Unit 4 . PHYA4 Fields and Further Mechanics
Written Examination . 75 marks,
1 ¾ hours
Section A is 25 multiple choice questions, each worth one mark.
Section B is a written paper of 4/5 structured questions and consists of 50 marks.
20% of the total A-Level marks available June
Unit 5 . One of Units PHA5A, PHA5B, PHA5C, PHA5D
Written Examination . 75 marks.
1 ¾ hours
Section A: Nuclear and Thermal Physics . 40 marks
Compulsory section 4/5 structured questions
Section B one of the following options.
Each paper has 4/5 structured questions and 35 marks.
Options: A - Astrophysics
B - Medical Physics
20% of the total A-Level marks (Section A 10%, Section B 10%) Available June only
Unit 6 . Internal Assessment Investigative and Practical Skills in A2 Physics
PHA6X, Externally Marked Route X . 55 marks
Practical Skills Verification (PSV . teacher verification)
Externally Marked Practical Assignment (EMPA . 55 marks)
10% of the total A-Level marks Available June only
Unit 1 PHYA1 Particles, Quantum Phenomena and Electricity
This module involves two contrasting topics in physics: particle physics and electricity. Through the study of these
topics, students should gain an awareness of the on-going development of new ideas in physics and of the
application of in depth knowledge of well-established topics such as electricity. Particle physics introduces students
to the fundamental properties and nature of matter, radiation and quantum phenomena. In contrast, the study of
,electricity in this module builds on and develops previous GCSE studies and provides opportunities for practical work
and looks into important applications.
Syllabus extract:
Constituents of the atom
Proton, neutron, electron.
Their charge and mass in SI units and relative units.
Specific charge of nuclei and of ions.
Atomic mass unit is not required.
Proton number Z, nucleon number A, nuclide notation, isotopes
Stable and unstable nuclei
The strong nuclear force; its role in keeping the nucleus stable; short-range attraction to about 3
fm, very-short range repulsion below about 0.5 fm;
Equations for alpha decay and β- decay including the neutrino.
Particles, antiparticles and photons
Candidates should know that for every type of particle, there is a corresponding antiparticle.
They should know that the positron, the antiproton, the antineutron and the antineutrino are the
antiparticles of the electron, the proton, the neutron and the neutrino respectively.
Comparison of particle and antiparticle masses, charge and rest energy in MeV.
Photon model of electromagnetic radiation, the Planck constant, E = hf =hc/λ
Knowledge of annihilation and pair production processes and the respective energies involved.
The use of E = mc2 is not required in calculations.
Particle interactions
Concept of exchange particles to explain forces between elementary particles
The electromagnetic force; virtual photons as the exchange particle.
The weak interaction limited to β-, β+ decay, electron capture and electron-proton collisions; W+
and W- as the exchange particles.
Simple Feynman diagrams to represent the above reactions or interactions in terms of particles
going in and out and exchange particles.
Classification of particles
Hadrons: baryons (proton, neutron) and antibaryons (antiproton and antineutron) and mesons
(pion, kaon).
Hadrons are subject to the strong nuclear force.
Candidates should know that the proton is the only stable baryon into which other baryons
eventually decay; in particular, the decay of the neutron should be known.
Leptons: electron, muon, neutrino (electron and muon types).
Leptons are subject to the weak interaction.
Candidates will be expected to know baryon numbers for the hadrons.
Lepton numbers for the leptons will be given in the data booklet.
Quarks and antiquarks
Up (u), down (d) and strange (s) quarks only.
Properties of quarks: charge, baryon number and strangeness.
Combinations of quarks and antiquarks required for baryons (proton and neutron only),
antibaryons (antiproton and antineutron only) and mesons (pion and kaon) only.
Change of quark character in β-and β+ decay.
, Application of the conservation laws for charge, baryon number, lepton number and strangeness
to particle interactions. The necessary data will be provided in questions for particles outside
those specified.
Particles and Radiation
Constituents of the Atom
Basic Structure of the Atom
The structure of the atom was unknown until the early 20 th century:
The nucleus consists of protons and neutrons at the
center of the atom.
Protons are (+) charged while neutrons are neutral. Both
have similar masses
Electrons are (-) charged, 1/1800 the mass of
neutrons/protons, and in motion around the nucleus.
The Nuclear Atom
Rutherford thought (Helium nuclei) particles would be the ideal particle to probe the atom.
He developed his famous gold foil experiment to investigate the inner structure of the
atom. This classic diffraction experiment was conducted in 1911 by Hans Geiger and
Ernest Marsden at the suggestion of Ernest Rutherford.
particles were shot at a thin gold foil.
A zinc sulfide detection screen surrounding the foil would fluorescence whenever
radiation struck the screen. The gold foil had to be as thin as possible to avoid
multiple scatterings.
Geiger and Marsden expected to find that most of the alpha particles travel straight
through the foil with little deviation, with the remainder being deviated by a percent or
two. This thinking was based on the plum pudding model.
What they found, to great surprise, was that most of the particles passed right
through the foil, implying the atom is mostly empty space.
A few particles were wildly deflected, implying a large
concentration of (+) charge in the center of the atom.
Rutherford’s model of the atom included a dense,
positively charged nucleus containing protons.
Electrons were thought to orbit the nucleus like planets orbit the sun.
The Neutron
In 1932, Chadwick used particles to strike Be metal. A very
penetrating type of radiation was formed.
This type of radiation had no charge and had a similar mass to a
proton. It was called the neutron.
