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Section Number
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Topic
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Descriptor
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Topic 4: Waves
(10h)
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4.1 Travelling
Waves (3h)
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Waves
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4.1.1
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Describe a wave pulse and
a continuous travelling wave.
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Students should
be able to distinguish between the oscillations and
the wave
motion.
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4.1.2
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State that waves transfer
energy
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Students should
understand that there is no net motion of the medium
through which the wave
travels.
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4.1.3
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Describe and give
examples of transverse and longitudinal
waves.
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Students should
know that sound is a longitudinal wave and that light is
a transverse
wave.
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4.1.4
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Describe waves in two
dimensions, including the concepts of wave fronts
and rays.
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Wave
characteristics
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4.1.5
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Define
displacement, amplitude, period,
frequency, wavelength and wave
speed.
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4.1.6
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Describe the terms
crest, trough, compression and
rarefaction.
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4.1.7
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Draw and explain
displacement-time and displacement-position graphs
for transverse and
longitudinal waves.
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4.1.8
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Derive and apply the
relationship between wave speed, wavelength and
frequency.
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4.2 Wave
Properties (5h)
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Note: Although the
properties apply to all waves, students should be
familiar with the
particular cases of sound, light and water.
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Reflection,
refraction and transmission of waves
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4.2.1
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Describe the reflection
and transmission of one-dimensional waves at a
boundary between two
media.
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This should
include the sketching of incident, reflected and
transmitted waves,
and the cases of reflection at free and fixed
ends.
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4.2.2
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State Huygens'
principle.
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4.2.3
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Apply Huygens' principle
to two-dimensional plane waves to show that the
angle of incidence is equal to
the angle of reflection.
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4.2.4
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Explain refraction using
Huygens' principle.
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4.2.5
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Derive, using
Huygens' principle, Snell's law for
refraction.
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The concept of
refractive index is not required but the ratio of speeds
is expected.
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4.2.6
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State and apply Snell's
law.
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Wave
diffraction and interference
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4.2.7
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Explain and discuss
qualitatively, using Huygens' principle, the
diffraction of waves by
apertures and obstacles.
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The effect of
wavelength compared to obstacle size or aperture size
should be
discussed.
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4.2.8
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Describe examples of
diffraction.
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4.2.9
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State the principle of
superposition and explain what is meant by
constructive and destructive
interference.
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4.2.10
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Apply the principle of
superposition to find the resultant of two
waves.
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Only
one-dimensional situations need to be
considered.
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Doppler
effect
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4.2.11
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Describe the Doppler
effect.
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Only a simple
description of the effect for both sound and light is
required.
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4.3 Standing
Waves (2h)
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Nature and
production of standing waves
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4.3.1
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Describe the nature of
standing waves.
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4.3.2
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Explain the formation of
standing waves in one dimension.
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4.3.3
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Compare standing waves
and travelling waves.
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Boundary
conditions and resonance
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4.3.4
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Explain the concept of
resonance and state the conditions necessary for
resonance to
occur.
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4.3.5
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Describe the fundamental
and higher resonant modes in strings and open
and closed pipes.
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Note that
fundamental and first harmonic are interchangeable
terms.
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4.3.6
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Solve problems involving
the fundamental and higher harmonic modes for
stretched strings and open and
closed pipes.
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End correction
is not required.
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Topic 10: Wave
Phenomena (8h)
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10.1 Doppler
Effect (2h)
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10.1.1
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Describe and explain the
Doppler effect.
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Students should
recognize that in general the velocities of source
and/or detector
are specified with respect to the medium. They should
know however
that light in a vacuum is unique and, in this case, it is
the relative velocity
of source and detector that is relevant.
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10.1.2
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Construct wavefront
diagrams for moving-detector and moving-source
situations.
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10.1.3
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Derive the equations for
the Doppler effect for sound in the cases of a
moving detector and a moving
source.
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10.1.4
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Solve problems on the
Doppler effect for sound.
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Problems may
include both a moving source and a moving detector but
not both
simultaneously.
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10.2 Beats
(2h)
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10.2.1
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Explain the formation of
beats.
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Students should
be able to sketch the resultant waveform from the
superposition of two
component waves.
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10.2.2
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Derive the beat frequency
formula.
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10.2.3
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Solve problems involving
beats.
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10.3 Two-source
Interference of Waves (4h)
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10.3.1
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Explain, by means of the
principle of superposition, the interference pattern
produced by waves from two
coherent point sources.
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Water, light
and sound waves should be considered.
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10.3.2
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State the conditions
necessary to observe interference between two light
sources.
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10.3.3
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Outline Young's double
slit experiment for light and draw the intensity
distribution of the observed
fringe pattern.
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Restrict this
to the situation where the slit width is small compared to
the slit
separation so that diffraction effects on the pattern are
not considered.
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10.3.4
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Derive expressions for
the locations of the maxima and minima of the
double slit fringe
pattern.
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These include
the angular form sin £c = n£f/d and the form s =
£f D/d for locations
on a screen at distance D, involving the small angle
approximation.
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10.3.5
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Solve problems involving
two-source interference.
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