|
Section Number
|
Topic
|
Descriptor
|
|
Topic 1:
Physics and Physical Measurement (11h)
|
|
1.1 The Realm
of Physics (2h)
|
|
Range of
magnitudes of quantities in our universe
|
|
1.1.1
|
State (express)
quantities to the nearest order of magnitude.
|
|
|
1.1.2
|
State the ranges of
magnitude of sizes, masses and times that occur in the
universe, from smallest to greatest.
|
Sizes-from
10-15
m to
10+25
m (subnuclear
particles to extent of the visible universe).
Masses-from
10-30
kg to
10+50
kg (electron to
mass of the universe).
Times-from
10-23
s to
10+18
s (passage of
light across a nucleus to the age of the
universe).
|
|
1.1.3
|
State and compare the
order of magnitude of selected (significant) systems in the
universe.
|
Students should
become familiar with the order of magnitudes of significant
systems with which they deal, and aim to develop a
familiarity with the orders of magnitudes of important
masses, lengths, times and other quantities.
|
|
1.1.4
|
State (express) ratios of
quantities as differences of orders of magnitude.
|
For example,
the ratio of the diameter of the hydrogen atom to its
nucleus is about 105
times, or a
difference of five orders of magnitude.
|
|
1.2 Measurement
and Uncertainties (2h)
|
|
The SI system
of fundamental and derived units
|
|
1.2.1
|
State the fundamental
units in the SI system.
|
Students need
to know the following: kilogram, meter, second, ampere, mole
and kelvin.
|
|
1.2.2
|
Distinguish between, and
give examples of, fundamental and derived
units.
|
|
|
1.2.3
|
Convert between different
units for quantities.
|
For example, J
and kWh, J and eV, years and seconds, and between other
systems and SI.
|
|
1.2.4
|
State units in the
accepted SI format.
|
Use m
s-2
not m/s/s and m
s-1
not
m/s.
|
|
1.2.5
|
State values in
scientific notation and in multiples of units with
appropriate prefixes.
|
For example,
use nanoseconds or gigajoules.
|
|
Uncertainty and
error in experimental measurement
|
|
1.2.6
|
Describe, distinguish
between and give examples of random uncertainties and
systematic errors.
|
|
|
1.2.7
|
Distinguish between
precision and accuracy.
|
For example,
repeated measurements on a voltmeter may have great
precision in that they are highly reproducible with small
scatter and uncertainty, yet they may be inaccurate (for
example if the voltmeter has a zero offset
error).
|
|
1.2.8
|
Explain how the effects
of random uncertainties may be reduced.
|
Students should
be aware that systematic errors are not reduced by repeating
readings.
|
|
1.2.9
|
State random uncertainty
as an uncertainty range (±) and represent it
graphically as an "error bar".
|
|
|
1.2.10
|
Identify values of
quantities and results of calculations to the appropriate
number of significant digits.
|
The number of
significant digits should reflect the precision of the value
or of the input data to a calculation. Only a simple rule is
required: for multiplication and division, the number of
significant digits in a result should not exceed that of the
least precise value upon which it depends.
|
|
1.3
Mathematical and Graphical Techniques (3h)
|
|
Estimation
|
|
1.3.1
|
Estimate approximate
values of everyday quantities to one or two significant
digits and/or to the nearest order of
magnitude.
|
Reasonable
estimates for common quantities, eg dimensions of a brick,
mass of an apple, duration of a heartbeat or room
temperature are expected.
|
|
1.3.2
|
State and explain
simplifying assumptions in approaching and solving
problems.
|
For example,
reasonable assumptions that certain quantities may be
neglected, others ignored (eg heat losses, internal
resistance), or that behaviour is approximately
linear.
|
|
1.3.3
|
Estimate results of
calculations.
|
Examples:
174/118 ~ 180/120 =
3/2 = 1.5
or 6.3 x 7.6/4.9 ~ 6
x 8/5 = 48/5 ~ 50/5 ~ 10.
|
|
Graphs
|
|
1.3.4
|
Construct graphs from
data, choosing suitable scales for the axes.
|
Include or
suppress the zero on an axis as appropriate.
|
|
1.3.5
|
Draw qualitative graphs
to represent dependencies and interpret graph
behaviour.
|
Students should
be able to give a qualitative physical interpretation of a
particular graph, eg as the potential difference increases,
the ionization current reaches a maximum.
|
|
1.3.6
|
Determine the values of
physical quantities from graphs.
|
Include
measuring and interpreting the slope (gradient), intercepts
and area under a curve, and stating the units for these
quantities.
|
|
1.3.7
|
Draw best-fit lines to
data points on a graph.
|
These can be
curves or straight lines as appropriate. Fitting by eye is
expected. Mathematical fitting is not required. Students
should not join data points with segments.
|
|
Graphical
analysis and determination of relationships
|
|
1.3.8
|
Transform equations into
generic straight-line form y = mx + c and plot the
corresponding graph.
|
This can
include plotting various functions of the variables such as
reciprocals, powers and roots. Logarithmic functions are not
required.
|
|
1.3.9
|
Analyse a straight-line
graph to determine the equation relating the variables.
|
The parameters
of the original function can be obtained from the slope m
and intercept c.
|
|
1.4 Vectors and
Scalars (4h)
|
|
Note: Although vectors
are mentioned here at the beginning of the physics
syllabus, this does not
necessarily represent the order in which they should
be
taught. Vectors may be
developed within other sections, for example in
the
context of particular
quantities such as force, displacement or
velocity.
|
|
1.4.1
|
Distinguish between
vector and scalar quantities, and give examples of
each.
|
When expressing
a vector as a symbol, students should adopt a recognized
notation.
|
|
1.4.2
|
Draw arrows of
appropriate length and direction to represent vector
quantities.
|
|
|
1.4.3
|
State vector quantities
either in terms of magnitude and direction or by their
components along chosen axes.
|
|
|
1.4.4
|
Add and subtract vector
quantities by the graphical method.
|
Add and
subtract accurately by construction, or approximately, if an
estimate is required. Multiplication and division of vectors
by scalars is also required.
|
|
1.4.5
|
Resolve vectors into
perpendicular components along chosen axes.
|
For example,
resolving parallel and perpendicular to an inclined plane.
Choose appropriate axes along which to resolve according to
the needs of the physical situation.
|
|
1.4.6
|
Interpret the physical
meaning of vector components where
appropriate.
|
For example,
interpret vertical and horizontal components of velocity in
projectile motion, or force components along and
perpendicular to an inclined plane.
|
|
1.4.7
|
Add two or more vectors
by the method of components.
|
First resolve
into components, then add the components and recombine them
into a resultant vector. Pythagoras' theorem and basic
trigonometry are required but not the sine and cosine
rules.
|
|
1.4.8
|
Solve problems involving
the vector nature of physical quantities.
|
Problems may
involve the vector nature of quantities such as
displacement, velocity, acceleration, momentum, force and
fields.
|
|
Topic 7:
Measurement and Uncertainties (2h)
|
|
7.1 Graphical
Analysis (1h)
|
|
Logarithmic
functions
|
|
7.1.1
|
Transform equations
involving power laws and exponentials into the generic
straight line form y = mx + c and plot the
corresponding log-log and semi-log graphs from the
data.
|
The use of
log-linear and log-log graph paper is not
required.
|
|
7.1.2
|
3 Analyse log-log
and semi-log graphs to determine the equation relating two
variables.
|
Students should
be able to determine the parameters of the original equation
from the slope and the intercept.
|
|
7.2
Uncertainties (1h)
|
|
Uncertainties
in calculated results
|
|
7.2.1
|
1 State
uncertainties as absolute, fractional and percentage
uncertainties.
|
|
|
7.2.2
|
Determine the
uncertainties in results calculated from quantities with
uncertainties.
|
A simple
approximate method rather than root mean square calculations
is sufficient to determine maximum uncertainties. For
functions such as addition and subtraction, absolute
uncertainties can be added. For multiplication, division and
powers, percentage uncertainties can be added. For other
functions (eg trigonometrical functions) the mean, highest
and lowest possible answers can be calculated to obtain the
uncertainty range. If one uncertainty is much larger than
others, the approximate uncertainty in the calculated result
can be taken as due to that quantity alone.
|
|
Uncertainties
in graphs
|
|
7.2.3
|
Determine the
uncertainties in the slope and intercepts of a straight-line
graph.
|
Students should
be able to draw lines of minimum and maximum fit to the data
points, plus error bars.
|