| Syllabus |
Notes |
Experimental Work |
Wave propagation. Nature
of motions in longitudinal and transverse progressive waves. Relation between 
and
f. Velocity of propagation of mechanical waves along stretched
strings or springs and in solids. |
Questions will not be set on the equation ,
but an understanding of the variation of displacement with time (x
constant) and with distance (t constant) in a progressive wave is
expected. Factors affecting the speed of propagation. The expression
and 
(proofs not required). |
E5 Investigation of the factors affecting the speed of
transverse progressive waves along a slinky spring (NAP 4.5a/D4a). |
| Wave phenomena |
Familiarity with ripple tank experiments is assumed from
lower form work. |
|
| Huygens' principle |
Explanation of laws of reflection and refraction. |
|
| Reflection |
Examples to include brief discussion of radar, sonar
and long distance propagation of radio waves by reflection from the ionosphere.
Phase change on reflection, illustrated for example, using a slinky spring. |
|
| Refraction |
Refraction as a result of change in wave speeds. Refractive
index in terms of speeds. |
|
| Polarisation |
Polarisation by selective absorption, reflection and
scattering. Practical applications to include polaroid spectacles, VHF
and UHF antennas (briefly). |
E6 Polarisation of light by (a) reflection from a shiny
surface
(b) absorption using a sheet of polaroid; and
(c) scattering using cloudy water (NAP 8.15/J21d). |
| Superposition |
Mathematical treatment not required. |
E7 Superposition of transverse waves on a slinky spring. |
| Beats |
Qualitative treatment Use in tuning. |
E8 Observation of beats on a CRO. |
| Diffraction |
Diffraction of light at apertures (simple qualitative
treatment only). |
E9 Looking at a lamp through a slit or a pin-hole to
study how the diffraction patterns depend on
(a) the shape of the aperture;
(b) the size of the aperture; and
(c) the wavelength of light.(NAP 8.1a/J1). |
| Interference |
Two-source interference with quantitative treatment for
maxima and minima. Conditions for observable interference. Practical applications
of interference to include the blooming of lenses and the testing of the
flatness of a surface (very briefly). Quantitative treatment of interference
effects at normal incidence in parallel- sided and wedge-shaped thin films.
Everyday example to include the colours of oil films and soap bubbles.
Newton's rings (qualitatively). Plane transmission grating as an interference
system. Use of the formula . Proportionality between
intensity and square of the amplitude (by analogy with harmonic oscillator
and energy delivered by an alternating current). Energy distribution in
interference patterns. |
E10 Estimation of the wavelength of light using (a) double
slit, and
(b) plane diffraction grating. (Nat Phil Workbook 5)
E11 Observation of Newton's rings and interference fringes in soap
films.
E12 Investigation of the amplitude and energy distribution in an
interference pattern of sound waves (NAP 8.7/J4). |
| The electromagnetic spectrum |
Knowledge of approximate frequency and wavelength of
all members of the spectrum and their common properties. |
|
| Stationary waves. Modes
of vibrations of strings and air columns. Harmonics and the quality of
sound. |
Graphical treatment only. |
E13 Demonstration of stationary waves on a rubber cord
and in a springs. (NAP 4.15, 4.16/D 16, D17. |
| Acoustics, intensity and loudness.
The decibel. Velocity of sound. |
Pressure and displacement in sound waves. Frequency response
of the ear. Relationship between intensity and loudness. Thresholds of
hearing and pain. Noise pollution (very briefly). Typical noise levels
in everyday life. Absorption of sound and sound proofing. Velocity of sound
Order of magnitude of speed of sound in solids, liquids and gases. Knowledge
of  not required. |
E14 Measurement of the speed of sound in sir by Kundt's
tube (e.g. NAP 4.16a/D 17a). |
| Doppler effect |
Quantitative treatment (change in the observed frequency
and wavelength) for a stationary medium and movement along the source-observer
line. Real life examples (police cars, ambulances and radar speed traps,
galaxy red shift indicating expanding universe, all treated qualitatively). |
|
| Optical instruments |
Qualitative understanding of how optical instruments
work (using simple ray diagrams only). |
For the purpose of the practical examination familiarity
with use of concave and convex mirrors, converging and diverging lenses,
and prisms is expected but full instruction on procedure will be given
and knowledge of particular methods is not required. |
| Magnifying glass |
Magnifying powers of magnifying glass, microscope and
refracting telescope considered as ratio of visual angles subtended by
the image and the object (as obtained from simple ray diagrams). |
|
| Microscope |
Two-lens type only. Formation of image at least distance
of distinct vision. |
|
| Refracting telescope |
Two-lens type only. Formation of image at infinity. |
|
| Grating spectrometer |
Qualitative explanation of the functions of the collimator
and the telescope using ray diagrams. Use in simple spectral analysis. |
|