7/25/2019 Physics Notes From Ideas to Implementation
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From Ideas to Implementation
Contents1. Increased understandings of cathode rays led to the
development of television
..............................................................................................................................
3
Explain why the apparent inconsistent behaviour of cathoderays
caused
debate as to whether they were charged particles or
electromagnetic waves...3
Explain that cathode ray tubes allowed the manipulation of a
stream of
charged
particles................................................................................................3
Identify that moving charged particles in a magnetic eld
experience a force. .3
Identify that charged plates produce an electric
eld........................................3
Describe uantitatively the force acting on a charge moving
through amagnetic eld F ! v" sin
...............................................................................3
Discuss ualitatively the electric eld strength due to a point
charge# positive
and negative charges and oppositely charged parallel
plates............................3
Describe uantitatively the electric eld due to oppositely
charged parallel
plates..................................................................................................................3
$utline %homson&s experiment to measure the charge'mass
ratio of an electron
...........................................................................................................................
3
$utline the role
of(..............................................................................................3
) Electrodes in the electron
gun......................................................................3
) %he de*ection plates or
coils........................................................................3
) %he *uorescent screen in the cathode ray tube of conventional
%+ displays
and
oscilloscopes............................................................................................3
,. %he reconceptualisation of the model of light led to an
understanding of the
photoelectric e-ect and blac body
radiation......................................................../
Describe 0ert&s observation of the e-ect of a radio wave on
a receiver and the
photoelectric e-ect he produced but failed to
investigate................................./
$utline ualitatively 0ert&s experiments in measuring the
speed of radio
waves and how they relate to light
waves........................................................../
Identify 2lanc&s hypothesis that radiation emitted and
absorbed by the walls
of a blac body cavity is
uantised...................................................................../
Identify Einstein&s contribution to uantum theory and its
relation to blac body
radiation.............................................................................................................
/
Explain the particle model of light in terms of photons with
particular energy
and
freuency..................................................................................................../
Identify the relationships between photon energy# freuency#
speed of light
and wavelength( E ! hf and c !
f...................................................................../
1
7/25/2019 Physics Notes From Ideas to Implementation
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3. 4imitations of past technologies and increased research into
the structure of
the atom resulted in the invention of
transistors...................................................5
Identify that some electrons in solids are shared between atoms
and move
freely..................................................................................................................
5
Describe the di-erence between conductors# insulators and
semiconductors interms of band structures and relative electrical
resistance................................5
Identify absences of electrons in a nearly full band as holes#
and recognise that
both electrons and holes help to carry
current...................................................5
6ompare ualitatively the relative number of free electrons that
can drift........5
From atom to atom in conductors# semiconductors and
insulators....................5
Identify that the use of germanium in early transistors is
related to lac of
ability to produce other materials of suitable
purity...........................................5
Describe how 7doping& a semiconductor can change its
electrical properties....5
Identify di-erences in p and n8type semiconductors in terms of
the relative
number of negative charge carriers and positive
holes......................................5
Describe di-erences between solid state and thermionic devices
and discuss
why solid state devices replaced thermionic
devices.........................................5
/. Investigations into the electrical properties of particular
metals at di-erent
temperatures led to the identication of superconductivity and
the exploration of
possible
applications.............................................................................................9
$utline the methods used by the "raggs to determine crystal
structure...........9
Identify that metals possess a crystal lattice
structure......................................9
Describe conduction in metals as a free movement of electrons
unimpeded by
the
lattice...........................................................................................................
9
Identify that resistance in metals is increased by the presence
of impurities and
scattering of electrons by lattice
vibrations........................................................9
Describe the occurrence in superconductors below their critical
temperature of
a population of electron pairs una-ected by electrical
resistance......................9
Discuss the "6:
theory.......................................................................................9
Discuss the advantages of using superconductors and identify
limitations totheir
use.............................................................................................................
9
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