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Section Number
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Topic
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Descriptor
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Topic 2:
Mechanics (24h)
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Kinematic
concepts
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2.1.1
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Define
displacement, velocity, speed and
acceleration.
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Quantities
should be identified as scalar or vector
quantities.
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2.1.2
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Define and explain the
difference between instantaneous and average
values of speed,
velocity and acceleration.
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2.1.3
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Describe an object's
motion from more than one frame of
reference.
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Students should
be familiar with the term relative velocity and
should be able
to calculate relative velocities in one
dimension.
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Graphical
representation of motion
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2.1.4
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Draw and analyse
distance-time graphs, displacement-time graphs,
velocity-time graphs and
acceleration-time graphs.
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Students should
be able to sketch and label these graphs for various
situations. They should
also be able to write descriptions of the motions
represented by such
graphs.
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2.1.5
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Analyse and calculate the
slopes of displacement-time graphs and velocity-
time graphs, and the areas under
velocity-time graphs and acceleration-time
graphs. Relate these to the
relevant kinematic quantity.
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Uniformly
accelerated motion
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2.1.6
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Determine the velocity
and acceleration from simple timing
situations.
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Students should
be able to interpret data from devices such as a light
gate, strobe
photograph or ticker timer. Analysis may involve graphing
the data, taking
measurements and applying kinematics
concepts.
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2.1.7
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Derive the equations for
uniformly accelerated motion.
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2.1.8
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Describe the vertical
motion of an object in a uniform gravitational
field.
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2.1.9
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Describe the effects of
air resistance on falling objects.
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Only
qualitative descriptions are expected. Students should
understand the term
terminal velocity.
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2.1.10
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Solve problems involving
uniformly accelerated motion.
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2.2 Forces and
Dynamics (5h)
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Forces and
free-body diagrams
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2.2.1
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Describe force as the
cause of deformation or velocity change.
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2.2.2
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Identify the forces
acting on an object and draw free-body diagrams
representing the forces
acting.
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Each force
should be labelled by name or given a commonly accepted
symbol. Vectors
should have lengths approximately proportional to their
magnitudes.
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2.2.3
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Resolve forces into
components.
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2.2.4
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Determine the resultant
force in different situations.
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2.2.5
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Describe the behaviour of
a linear spring and solve related problems.
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Spring
combinations will not be assessed.
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Newton's first
law
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2.2.6
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State Newton's first law
of motion.
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2.2.7
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Describe examples of
Newton's first law.
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Equilibrium
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2.2.8
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State the condition for
translational equilibrium.
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2.2.9
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Solve problems involving
translational equilibrium.
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Newton's second
law
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2.2.10
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State Newton's second law
of motion.
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Students should
be familiar with the law in both the forms F = ma
and F =
Æp/
Æt.
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2.2.11
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Solve problems involving
Newton's second law.
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Newton's third
law
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2.2.12
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State Newton's third law
of motion.
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Students should
understand that when two bodies A and B interact, the
force that A exerts on
B is equal and opposite to the force that B exerts on
A.
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2.2.13
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Discuss examples of
Newton's third law.
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2.3 Inertial
Mass, Gravitational Mass and Weight (1h)
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2.3.1
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Define inertial
mass.
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Students should
describe inertial mass as the ratio of resultant force
to acceleration.
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2.3.2
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Compare gravitational
mass and inertial mass.
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Students should
understand that although the concepts of
gravitational mass
and inertial mass are different, they have identical values.
A simple argument
should be given to show that the equivalence of
gravitational mass
and inertial mass accounts for objects having the same value
for freefall acceleration.
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2.3.3
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Discuss the concept of
weight.
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Students should
understand that usage of the term weight can
be ambiguous, eg
weight can mean the gravitational force mg and the reading
on a supporting
scale; these have different values in non-equilibrium
situations.
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2.3.4
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Distinguish between mass
and weight.
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2.4 Momentum
(4h)
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2.4.1
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Define linear momentum
and impulse.
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2.4.2
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State the law of
conservation of linear momentum.
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2.4.3
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Derive the law of
conservation of momentum for an isolated system
consisting of two interacting
particles.
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The law is
derived by applying Newton's second law to each particle
and Newton's
third law to the system.
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2.4.4
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Solve problems involving
momentum and impulse
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Students should
be familiar with elastic and inelastic collisions and
explosions.
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2.5 Work,
Energy and Power (6h)
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Work
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2.5.1
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Define
work.
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Students should
be familiar with situations where the displacement is
not in the same
direction as the force.1
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2.5.2
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Determine the work done
by a non-constant force by interpreting a force-
displacement
graph.
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2.5.3
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Solve problems involving
the work done on a body by a force.
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Energy and
power
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2.5.4
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Define kinetic
energy.
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2.5.5
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Describe the concepts of
gravitational potential energy and elastic potential
energy.
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2.5.6
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State the principle of
conservation of energy.
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2.5.7
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List different forms of
energy and describe examples of the transformation
of energy from one form into
another.
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2.5.8
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Define
power.
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2.5.9
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Define and apply the
concept of efficiency.
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2.5.10
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Solve work, energy and
power problems.
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2.6 Uniform
Circular Motion (2h)
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2.6.1
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Draw a vector diagram to
show that the acceleration of a particle moving
with uniform speed in a circle is
directed toward the centre of the circle.
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2.6.2
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State the expression for
centripetal acceleration.
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2.6.3
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Identify the force
producing circular motion in various
situations.
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Examples
include gravitational force (acting on the moon) and
friction (acting
sideways on the tyres of a car turning a
corner).
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2.6.4
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Solve problems for
particles moving in circles with uniform
speed.
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Topic 8:
Mechanics (15h)
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8.1 Projectile
Motion (3h)
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8.1.1
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State the independence of
the vertical and horizontal components of motion
for a projectile in a uniform
field.
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8.1.2
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Describe the trajectory
of projectile motion as parabolic in the absence of
friction.
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Proof of the
parabolic nature of the trajectory is not
required.
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8.1.3
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Solve problems on
projectile motion.
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Problems may
involve projectiles launched horizontally or at any angle
above or below
horizontal. Applying conservation of energy may provide a
simpler solution
to some problems than using projectile motion
kinematics equations.
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8.2 Gravitation
(5h)
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Gravitational
force and field
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8.2.1
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State Newton's law of
universal gravitation.
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Students should
be aware that the masses in the force law are point
masses not
extended masses, but that the interaction between two
spherical masses is
the same as if the mass were concentrated at the centres of
the spheres.
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8.2.2
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Define gravitational
field strength.
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Students should
recognize the vector nature of gravitational
fields.
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8.2.3
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Derive an expression for
the gravitational field as a function of distance
from a point
mass.
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This includes
the field outside a spherical mass. See
8.2.1.
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8.2.4
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Derive an expression for
gravitational field at the surface of a
planet.
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Students should
also understand how the gravitational field strength
and the
acceleration due to gravity at the surface are
related.
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8.2.5
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Solve problems involving
gravitational forces and fields.
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Vector addition
is required to find the gravitational field strength due
to more than one
mass.
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Gravitational
energy and potential
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8.2.6
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Define gravitational
potential energy and gravitational
potential.
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Students should
understand that the work done in moving a mass
between two
points in a gravitational field is independent of the path
taken and that gravitational
potential energy is taken to be zero at
infinity.
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8.2.7
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State the expression for
gravitational potential due to a point mass.
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8.2.8
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Explain the concept of
escape speed.
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8.2.9
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Derive an expression for
the escape speed of an object from the surface of a
planet.
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8.2.10
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Solve problems involving
gravitational potential energy and gravitational
potential.
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These should
include problems on escape speed.
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8.3 Orbital
Motion (2h)
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Note: Although orbital
motion can be circular, elliptical or parabolic, this
section only deals with circular
orbits. This section is not fundamentally new
physics, but an application which
synthesizes ideas from gravitation, circular
motion, dynamics and
energy.
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8.3.1
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State that gravitation
provides the centripetal force for circular orbital
motion.
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8.3.2
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State Kepler's third law:
the law of periods.
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8.3.3
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Derive Kepler's third
law.
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This derivation
is for the case of circular orbits and assumes Newton's
law of universal
gravitation.
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8.3.4
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Derive expressions for
the kinetic, potential and total energy of an
orbiting satellite.
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8.3.5
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Draw graphs showing the
variation of the kinetic energy, gravitational
potential energy and total energy
with orbital radius of a satellite.
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8.3.6
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Discuss the concept of
weightlessness in both orbital motion and in free
fall.
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8.3.7
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Solve problems involving
orbital motion.
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