1. Keith Kiely
Physics Study
Keith Kiely
2011-2013
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2. Keith Kiely
Heat and Temperature
Unit of Temperature:
 Kelvin (K)
Thermometric Properties
A thermometric property is a measurable property of a body that changes the
temperature
Examples are:
 The length of liquid in a tube
 The resistance of a wire or a thermistor
 The EMF of a thermocouple
 The colour of some substances
 The pressure and volume of gas
Heat capacity:
The heat capacity of a body is the amount of energy needed to raise the temperature of
a body by 1K
The pacific heat capacity (c) of a substance is the amount of energy needed for the
temperature
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3. Keith Kiely
Latent Heat:
Latent heat is when heat is absorbed or released when it is in the process of changing
states.
Heat Transfer:
 Conduction
 Convection
 Radiation
Conduction:
This is the transfer of heat within a body without the movement of particles within the
body itself
Convection:
This is the transfer of heat within a body also with the movement of the particles in
the body.
Radiation:
Is the transfer of energy into an empty space, it is how heat and light from the sun
reach earth
Key Definitions:
 Heat Capacity (C)
 Specific Heat Capacity (c)
 Latent Heat (L)
 Specific Latent Heat (l)
 Conduction
 Convection
 Radiation
 Thermometric Properties
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4. Keith Kiely
Mechanics
Work, Energy and Power:
Work is done when a force moves an object a certain distance
Work is also the force multiplied by distance
Energy is the ability to do work
Two forms of energy are:
 Kinetic Energy (Ek)
 Potential Energy (Ep)
Power is:
 The rate work is done
 The rate at which energy is changed from one form to another
Power is energy divided by time
Linear Motion:
In mechanics we make use of:
 Scalar Quantities
 Vector Quantities
Scalars are quantities that only have magnitude
Vectors are having both magnitude and direction
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5. Keith Kiely
Conservation of Momentum
For a collision occurring between object 1 and object 2 in an isolated system, the total
momentum of the two objects before the collision is equal to the total momentum of
the two objects after the collision. That is, the momentum lost by object 1 is equal to
the momentum gained by object 2.
Newton’s Law of Motion:
1. A body will continue in a state of rest unless a force is upon it
2. The rate in the change of momentum depends on the force applied to it
3. If body a makes a force against another body, both bodies have an equal force
First Law:
This is demonstrated by space travel.
In the absence of air, a spacecraft traveling seven thousand meters per second can do
so without engines.
It will travel till a force is applied to stop it
Second Law:
This is demonstrated by seat belts.
When a person is thrown forward, the belt expands slightly
This extends the time over which the person is slowing down,
This decreases the value of the acceleration and reduces the force
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6. Keith Kiely
Third Law:
Seen from a rocket when a large force towards the rear. It creates an equal but
opposite force. This is why it moves
Circular Motion:
A body that travels an equal distance in equal amounts of time along a circular path
has a constant speed but not constant velocity. This is because velocity is a vector and
thus it has magnitude as well as direction
Acceleration:
This is when an object changes its direction, the velocity changes with it. It is known
as centripetal acceleration and its direction is towards the centre. It gives Rise to the
Centripetal force
Centripetal acceleration:
This is the acceleration of a body moving in a motion of a circle. The direction is
towards the centre of the circle.
Centripetal force:
Is the force on a body in a circular motion and the direction is towards the centre of
the circle.
Plants and Gravity:
This states that the force of attraction between any two masses is proportional to the
product of the masses.
Weight:
The weight of the body is the gravitational force of the body.
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7. Keith Kiely
Simple Harmonic Motion:
It is when any motion where the acceleration is proportional to the distance from its
equibrium
Hooks Law:
Hooke’s law is when the restoring force on a spring is the same as the extension on
the spring
Hookes Law Apparatus
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8. Keith Kiely
Hookes Law Graph
Boyles Law:
States that when the temperature on a gas is constant, the pressure on its volume is
proportional.
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9. Keith Kiely
Boyles Law Apparatus
Archimedes Principle:
This states that a body immersed in a fluid will have an upthrust equal to the weight
Moments of a Force:
The moment of a force is equal to the magnitude of the force multiplied by the
perpendicular distance from the axis.
The moment of a force tells us about the ability to make something turn.
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10. Keith Kiely
Light, Sound and Waves
Reflection:
The angle of incidence is equal to the angle of reflection
The incidence ray, the normal ray and the reflected ray are all on the same plane
Image Formation:
A real image is formed by the insertion of light rays and can be formed by a
screen
An image is formed by this insertion of light rays and can’t be formed on a screen
Curved Mirrors:
A light ray parallel to the principle axis is reflected trough the focal point
A light ray through the focal point reflects parallel to the axis.
A light ray incident at the pole clearly reflects according to the laws of reflection
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11. Keith Kiely
Refraction:
Laws of Refraction:
 The incident ray, the normal ray and the refracted ray are all in the same plane
 For any pair of media, the angle of the incidence is proportional to the angle of
refraction.
 When light moves from a low dense medium to a more dense medium it bends
to the normal
 If it moves into a denser medium it moves away from the normal.
Refraction is caused by the change in the speed of light.
Reflection:
 The Internal Reflection occurs when the angle of incidence in a dense material
is greater than the critical angle and light is reflected back into the original
material.
 The critical angle is the angle of incidence of where the corresponding angle
or refraction is 90˚
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12. Keith Kiely
Converging Lenses:
The light is refracted inward on both entering and leaving lenses. This causes the
converging effect. All the light that hits the lens passes through the single point
known as the vocal point
Diverging Lenses:
A lens that causes a beam of parallel rays to diverge afterrefraction, as from a virtual
image; a lens that has a negative focal length.
Waves:
Doppler Effect is the apparent change in the frequency of a wave because of relative
motion between the observer and the source
A redshift is a shift in the frequency of a photon toward lower energy, or longer
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13. Keith Kiely
wavelength. The redshift is defined as the change in the wavelength of the light
divided by the rest wavelength of the light.
The Doppler Redshift results from the relative motion of the light emitting object and
the observer. If the source of light is moving away from you then the wavelength of
the light is stretched out, i.e., the light is shifted towards the red. These effects,
individually called the blueshift and the redshift are together known as Doppler shifts
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