The ability to do work or cause change What are the different forms of Energy Energy has a number of different forms all of which measure the ability of an object to do work on or change another object ID: 904669
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Slide1
What is Energy?
.
Slide2What is Energy?
The ability to do work or cause change.
Slide3What are the different forms of Energy?
Energy has a number of different forms, all of which measure the ability of an object to do work on or change another object.
In other words, there are
different ways
that an object can possess energy.
Slide4Forms of Energy
All types of energy can be transformed into other forms.
Mechanical
Potential Kinetic
Chemical
Nuclear
Light/Radiant
Thermal
Sound
Electrical
Slide5Energy
Kinetic: The energy of an object due to it’s
motion
the greater the
mass
or
speed
, the greater it’s kinetic energy
Potential: The energy of an object due to it’s positionthe greater the mass or
height
, the greater it’s potential energy
Slide6A waterfall has both kinetic and potential energy.
The water at the top of the waterfall has stored potential energy.
Once the water leaves the top of the waterfall, the potential energy is changed into kinetic energy.
Example
Slide7Mechanical Energy
Combined
total
of
potential
and
kinetic
energy of an object
Chains pulling up the roller coaster, hammer hitting a nail, turning on a flashlight
Slide8Chemical Energy
Energy that comes from
chemical
changes
Stored in the
connections
between
atomsWe use food for chemical energy so we can perform
Fuels produce chemical energy
Fire works
Batteries have
stored
chemical energy which changes to
electrical
energy when turned on
Slide9Nuclear Energy
Energy stored in the
nucleus
of an atom (holds the atom together)
Produced when an atom
splits
apart (
Fission
)Nuclear power plantProduced when 2 atoms join to form 1 atom (
Fusion
)
The sun’s energy is produced when Hydrogen (H) atoms fuse to form Helium (He).
Slide10Electrical Energy
Associated with the movement of
electrons
through a
wire
or
circuit
Produced by
electric chargesPower running the chains that pull up the roller coaster generator has a loop of wire that spins creating an electrical current
Appliances use it to work
Slide11Radiant Energy
Also called Light or Electromagnetic Energy
Travels in waves and can move through
empty space
Energy carried by light and other kinds of EM waves
Sunshine, Visible Light, x-rays
Slide12Light / Radiant Energy
Travels in the form of
electromagnetic waves
, most of which we can not see.
Classified by wavelength (pg 309 SS)
Gamma rays have the shortest wavelength
Radio waves have the longest
Visible light is in the middle
All the colors of the rainbowWhen they are all combined you see them as white lightRoy G Biv (name to remember order of colors)
Electromagnetic Spectrum:
Full range of electromagnetic waves
Slide13Sound Energy
The energy of
vibrations
carried by
matter
(air, water,
solids
).
Sound waves canNOT travel through empty spaceTelephone
Slide14Thermal Energy
Total
Amount
of Kinetic Energy contained in all
particles
of a substance
The more
particles
a substance contains, the greater the thermal energyMore thermal Energy does not mean a
higher
temperature.
Ocean is massive, therefore has
more
thermal energy than a pot of boiling water, but is not
hotter
.
Wood fire produces heat
Slide15Energy Transformations
All types of energy can be
transformed
into other types.
Law of Conservation of Energy:
Energy can not be created or destroyed. It can only be changed into other forms of Energy.
Slide16Temperature and Heat
TEMPERATURE
The
measure
of the average kinetic energy of the particles in a substance. More kinetic energy = higher temperature
HEAT
The transfer of thermal energy between substances that are at different
temperatures.
Heat will transfer from the object with the
higher
temperature
to
the object with the
lower
temperature until the temperature is the same
Heat makes molecules
move faster
and
spread
. Heat spreads out in all directions.
Heat flows from warm water to the ice cubes, melting the ice as the water cools.
Slide17Transfer of Thermal Energy
Slide18Methods of Heat Transfer
CONDUCTION
CONVECTION
RADIATION
Slide19Conduction
Transfer of heat from a warmer substance to a cooler substance through direct contact
Energy from faster moving particles is transferred to slower moving particles until both are moving at the same speed and their temperature is
equalized
Conductor
: transfers heat very well (metal)
Insulator
: does not transfer heat very well (wood)
Slide20Conductors and Insulators
Conductor
:
Material through which energy can be transferred as heat
Metal is an excellent conductor, wood is not.
Insulator
:
Material that reduces or prevents the transfer of heat
“Bad Conductors”
.
Wood
Slide21Convection
Transfer of heat (thermal energy) within liquids and gases.
Heat always moves from warmer to cooler areas
Cold water on a hot stove
As the water on the bottom heats up, it becomes less dense (particles spread out)
Because the warm water is less dense than the cold water above it, the warm water rises and displaces the cold water, which sinks and warms.
Heat always moves from warmer to cooler areas
This movement of water is called a
Convection Current:
moves warm and cool molecules around until
they are evenly mixed an the same temp.
Slide22Convection
Slide23Radiation
Transfer of energy as electromagnetic waves
Can occur in empty space
Moves heat around in waves
Sun releases some it’s heat energy as infrared waves
Infrared Waves: low frequency light wave that is invisible to humans but felt as heat. (toasters, heaters)
Slide24Green House Effect