Download Energy File

What is energy?
 The capacity or the power to do work
 It is associated with any change
 DON’T confuse it with force (to push or pull or twist
something)
Conservation of energy
 You cannot create energy out of nowhere
 Energy is simply transferred from one form to another
 Potential energy – stored energy (waiting to be
used)
 Kinetic energy – energy of motion (already being
used)
A Roller Coaster
 A roller coaster
speeds along its
track
 It has kinetic
energy because it is
moving
A Roller Coaster
 As it slows to a
stop at the top of
a hill, it has
potential
energy because
of where it is
 It has the
potential to
move because it is
above the ground
and has
somewhere to
go
Types of energy
 Kinetic – energy involving movement
 Nuclear – energy of the particles inside an atomic nucleus
 Sound – energy involving vibrations in the air that create
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noise
Gravitational – energy involving the ability to fall
downwards
Light – energy involving the production of visible light
Elastic – energy involving a stretched object with the ability
to return to its natural shape
Electrical – energy involving the movement of electrons
Chemical – energy involving chemical reactions
Heat – energy involving the movement of the particles
within a substance
What is Kinetic Energy?
o Energy due to a
object’s motion
The bowling ball has
kinetic energy.
When the ball strikes
the pins, kinetic energy
is transferred to the
pins!
Examples of Kinetic Energy
Gravitational Energy
Energy an object or
substance has because
of its position
Anything “up high”
What is Electrical Energy?
o Energy caused by
the movement of
electrons
o Easily transported
through power lines
and converted into
other forms of energy
What is Chemical Energy?
o Energy that is
available for release
from chemical
reactions.
The chemical bonds in
a matchstick store
energy that is
transformed into
thermal energy when
the match is struck.
Examples of Chemical Energy
What is Heat Energy?
o The heat energy of an
object determines how
active its atoms are.
A hot object is one whose atoms
and molecules are excited and
show rapid movement.
A cooler object's molecules and
atoms will show less movement.
Types of Energy – Road Runner Clips
 https://www.youtube.com/watch?v=Jnj8mc04r9E
 https://www.youtube.com/watch?v=3xCOaDyJIDQ
Classes of Energy
POTENTIAL
Stored energy
?
KINETIC
Energy of
motion
?
Classes of Energy
POTENTIAL
Stored energy
Gravitational, Nuclear,
Chemical, Elastic
KINETIC
Energy of motion
Kinetic, Electrical,
Sound, Light, Heat
Activity
 Design a poster or collage on your iPads of the 9 types
of energy
 For each type of energy:
 Find 3 examples
 Identify whether it is potential energy or kinetic energy
 Draw or find 1 or more pictures showing the energy
A battery powering a light bulb
Solar cells powering a fan
An operating electric heater
Rubber band powered toys
Spring-powered toys
Energy Transfers and Transformations
 All things possess energy even if they are not moving
 Energy cannot be created or destroyed – the amount of
energy in the universe is always the same
 Law of Conservation of Energy
 Energy can be stored (potential energy)
 Energy can be transferred to another object
 From a cricket bat to a ball
 Energy can be transformed into a different form
 From electrical energy to sound energy
Activity
 Complete the following table in your exercise books:
Object
What to do to release stored
energy
Potential energy is
usefully transformed
into…
Torch battery
Switch it on
Electrical energy, light
energy
Chocolate
Petrol
Dynamite
Olympic diver on platform
Match
Stretched elastic band
Activity
Activity
 Match the following scenarios/objects to the
appropriate energy transformation sequence
Object/Scenario
Transformations
Lamp
Electrical → heat
Door bell
Chemical → heat
Microwave
Electrical → sound
Photosynthesis
Chemical → heat and mechanical
Gas stove
Light → electrical
Solar battery
Electrical → heat and light
Car
Light → chemical
Activity
 Identify the Energy Transformations or Transfers in
the following examples:
Wasted energy
 In energy transfers and transformations, most of the
energy is converted is useful
 However, some of the conversions are not useful and wastes
the energy
Appliance
Useful energy conversion
Wasted energy
Microwave
Electrical to heat
Light, sound, heating
anything other than the food
Television
Electrical to light and sound
Heat
Hair dryer
Electrical to heat and kinetic
(moving the air)
Sound
Lightbulb
Electrical to light
Heat, sound
Efficiency
 The energy efficiency of an object is a measure of it’s
ability to provide useful energy
 This is usually expressed as a percentage