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Let’s number our INB correctly
• Left Side
• Even Numbers
• 64
• 66
• 68
• 70
• 72
• 74
• 76
• Right Side
• Odd Numbers
• 65
• 67
• 69
• 71
• 73
• 75
• 77
Energy in Our Lives
S8P2. Students will be familiar with the forms and
transformations of energy.
a.Explain energy transformation in terms of the Law of
Conservation of Energy.
b.Explain the relationship between potential and kinetic
energy.
c. Compare and contrast the different forms of
energy (heat, light, electricity, mechanical motion,
sound) and their characteristics.
Page 65
• Energy is the ability to do work or cause
change.
• According to the Law of Conservation of
Energy, energy CANNOT be created or
destroyed, but it CAN change forms
(transformation).
• There are 2 main types of energy:
Potential Energy (stored up energy) and
Kinetic Energy (moving energy)
All forms of energy fall into one of these
two categories.
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• Kinetic energy (K.E.), the energy of motion. An
object has to be moving to have kinetic energy.
The two factors that affect kinetic energy are:
mass and velocity.
• Greater mass = greater K.E.
• Less mass = less K.E.
• Greater velocity = greater K.E.
• Less velocity = less K.E.
• K.E. can be calculated using the formula:
• Kinetic Energy = ½ mass x velocity2
(where mass is in kg and velocity is in m/s)
Page 69
• Potential energy (G.P.E.) is the energy stored in
an object due to its position or condition. The
factors that affect gravitational potential energy
are: mass and height. A moving object can have
potential energy as well as kinetic energy.
• The higher an object is positioned, the greater the
G.P.E.
• The more mass an object has, the greater the G.P.E.
• G.P.E. can be calculated using the formula:
• G.P.E. = mass x height x gravity
(where mass is in kg, height is in m and gravity is 9.8 m/s2)
Page 66
• Copy problem and calculate:
• What is the kinetic energy of a 120kg object
moving at a velocity of 2m/s?
Top of Page 66
• What is the kinetic energy of a 120kg object
moving at a velocity of 2m/s?
• Kinetic Energy = ½ mass x velocity2
(where mass is in kg and velocity is in m/s)
• K.E. = ½ x 120 x 22
• K.E. = ½ x 120 x 4
• K.E. = 240 Joules
Page 66
• Copy problem and calculate:
• 1. What is the kinetic energy of a 2000kg object
moving at a velocity of 4m/s?
Page 66
• Copy problem and calculate:
• 1. What is the kinetic energy of a 2000kg object
moving at a velocity of 4m/s?
• 2. What is the kinetic energy of a 4kg bowling
ball moving at a speed of 3m/s?
Page 68
• Copy problem and calculate:
• What is the gravitational potential energy of a 2
kg vase resting on a shelf 3 meters high?
Top of Page 68
• Copy problem and calculate:
• What is the gravitational potential energy of a 2
kg vase resting on a shelf 3 meters high?
• Gravitational Potential Energy = mass x height x gravity
(where mass is in kg, height is in m and gravity is 9.8 m/s2)
• GPE = 2 x 3 x 9.8
• GPE = 6 x 9.8
• GPE =
58.8 Joules
Page 68
• Copy problem and calculate:
• 1. What is the gravitational potential energy of a
5 kg book resting on a desk 12 meters high?
Page 68
• Copy problem and calculate:
• 1. What is the gravitational potential energy of a
2 kg vase resting on a shelf 3 meters high?
• 2. What is the gravitational potential energy of a
5 kg book resting on a desk 12 meters high?
• 3. What is the GPE of a 100kg man standing on
top of a hill 80 meters high?
Page 71
• There Are Seven Major Forms of Energy:
Mechanical, Sound (Wave Motion),
Chemical, Electrical, Light (Radiant),
Thermal (Heat) and Nuclear. Each of these
can be classified as kinetic or potential or
both.
• Mechanical energy is the potential energy
and the kinetic energy added together. Ex –
running, plane flying, water falling on
waterfall, roller coaster going down a hill
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• Sound energy is caused by an object’s
vibrations. When an object vibrates, its
vibrations transmit through the air so
that we can hear it from another location.
Ex.- Music from guitar, person talking or
bird chirping
• Chemical energy is the energy stored in
the compounds of materials that
changes as its atoms are rearranged.
Ex.- food, gasoline, batteries
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• Electrical energy is the energy of moving
electrons. Ex.- lightning or electrical
outlets/appliances
• Light energy (Radiant energy or
Electromagnetic energy) is produced by
the vibrations of electrically charged
particles. These vibrations cause energy
to be transmitted. Ex.- sunlight
Page 77
• Thermal energy is all of the kinetic
energy due to random motion of the
particles that make up an object. Heat is
thermal energy.
• Nuclear energy, the energy that comes
from changes in the nucleus of an atom.
• Fission is when the nucleus of an atom is
split apart.
• Fusion is when the nucleus of two atoms
are joined or “fused” together.
Top Half of Page 70
• Make a 2-column T-chart and classify each form of
energy as kinetic energy or potential energy.
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Mechanical
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Mechanical
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Mechanical
Chemical
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Electrical
Mechanical
Chemical
Electrical
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Electrical
Light
Mechanical
Chemical
Electrical
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Electrical
Light
Thermal
Mechanical
Chemical
Electrical
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Electrical
Light
Thermal
Mechanical
Chemical
Electrical
Nuclear
Top Half of Page 70
Mechanical, Sound (Wave Motion), Chemical, Electrical,
Light (Radiant), Thermal (Heat) and Nuclear
Kinetic Energy Potential Energy
Mechanical
Sound
Electrical
Light
Thermal
Wind
Mechanical
Chemical
Electrical
Nuclear
Elastic
• S8P2. Students will be familiar with the forms
and transformations of energy.
• d. Describe how heat can be transferred through matter by
the collisions of atoms (conduction) or through space
(radiation). In a liquid or gas, currents will facilitate the
transfer of heat (convection).
Page 77
• Thermal Energy – the total kinetic energy
of the particles that make it up. It
depends on two factors: the amount of
material (mass) and the temperature.
• When heat is transferred, it is from the
higher temperature object to the lower
temperature object until they both reach
the same temperature. There are three
ways that heat is transferred:
conduction, convection and radiation.
Page 77
• Conduction is the transfer of thermal
energy from one substance to another
through direct contact (collision of
particles).
• Heat travels along a substance from
molecule to molecule (between two
materials that touch each other)
• Examples – hot sand touching feet, pan
on stovetop,
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• Convection is the transfer of thermal energy
by the movement of a liquid or a gas utilizing
convection currents.
• Convection currents are the vertical
movement of air or liquid currents due to
temperature variations. “Hot air rises” the more
dense air sinks forcing the less dense air upward
• Examples – radiator heater, convection oven
and ocean currents.
Page 79
• Radiation is the transfer of energy by
electromagnetic waves, such as visible
light and infrared waves, the movement
of heat in a wave-like motion through an
empty space.
• Examples – sunlight, heat from toaster,
heat from a light bulb, heat from a fire