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AS Module 1 Particles and Quantum Phenomena |
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Introduction
The two themes explored in this module are those
of particles and of electromagnetic radiation and quantum phenomena. The concept
of anti-particles is introduced as are quarks and anti-quarks. The particle and
the wave models are brought together. Most of this module consists of material
from the AS criteria for Physics and develops material studied in the Key Stage
4 science courses. |
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10.1 Particles |
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| 10.1.1 Constituents of the atom |
Proton, neutron,
electron
interactive
Atomic mass unit
is not required |
| 10.1.2 Evidence for existence of the nucleus |
Qualitative study of Rutherford scattering Proton number Z, nucleon number A, isotopes
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| 10.1.3 Particles, antipar
ticles and photons:
particle adventure: antiparticles
S-Cool: antimatter, particle accelerators pair production and annihilation
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Photon
model of electro
Weak interaction, limited to changes in which a proton changes to a neutron or vice versa
Pair production annihilation of a particle and its antiparticle releases energy; the use of E = mc2 is not required
Concept of exchange particles to explain forces between elementary particles
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| Beta decay | Simple Feynman diagrams to show how a reaction occurs in terms of particles going in and out and exchange particles: limited to B- decay, B+ decay, electron capture, neutrino – neutron collisions, antineutrino - proton collisions and electron – proton collisions |
| 10.1.4
Classification of particles
Hadrons and Leptons
S-Cool: Hadrons and Leptons |
baryons (proton, neutron)
mesons (pion, kaon)
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,
Candidates will not be required to remember, but will be expected to be familiar with, baryon numbers and lepton numbers for individual particles and antiparticles. |
| 10.1.5 Quarks and antiquarks
and more quarks |
Up (u), down (d) and strange (s) quarks only.
Properties of quarks: charge, baryon number and strangeness
Change of quark character in B- decay and B+ decay
Application of the conservation laws for charge, baryon number and strangeness to particle interactions |
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Some web sites that seem relevant |
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10.2 Electromagnetic radiation and quantum
phenomena |
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| 10.2.1
Refraction at a plane surface
S-Cool: refraction |
Refractive index, n; candidates are not expected to recall methods for determining refractive indices 1n2 = sinq1/ sinq2 =c1/c2 1n2 = n2 / n1 Total internal reflection including calculations of critical angle, sin qc = 1 / n Simple treatment of fibre optics including function of cladding with lower refractive index around central core limited to step index only; candidates should be familiar with
modern applications of fibre optics, e.g.
endoscopy,
com- muncations
etc. |
| 10.2.2 The
photo electric effect.
Photo electric effect - another link S-Cool: photo electric effect |
Treatment limited to energy consider- ations only; the stopping potential experiment is not required; work function f, photoelectric equation: hf
= f |
| 10.2.3 Collisions of electrons with atoms
how does a fluorescent lamp work? S-Cool: electron energy levels |
The electronvolt Under line spectra (e.g. of atomic hydrogen) as evidence of transitions between discrete energy levels Energy levels, photon emission hf
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| 10.2.4
Wave particle duality
S-Cool: wave particle duality |
Candidates should know that electron diffraction suggests the wave nature of particles and the photo electric effect
suggests the particle nature of electro
details of particular methods of showing particle diffraction are not expected
l = h / mv |
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Past module questions on Electromagnetic radiation and Quantum Effects plus mark schemes |
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Questions |
Answers |
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Conservation laws for charge, baryon number and strangeness |
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Refraction homework |
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Revision Resources |
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