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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...................................................................../
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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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7/25/2019 Physics Notes From Ideas to Implementation
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1. Increased understandings of cathode rays led to the
development of television
Identify that charged plates produce an electric eld
"etween two charged plates# a uniform ;strength is eual at all points681or +m81
