Energy
Definition? – From Wikipedia
• In physics, energy (from the Greek
ἐνέργεια - energeia, "activity, operation",)
is a scalar physical quantity that describes
the amount of work that can be performed
by a force.
http://en.wikipedia.org/wiki/Energy
What does scalar mean? – without direction.
What is work? – The force required to
move an object multiplied by the distance it
is moved.
Different forms of energy include:
kinetic,
potential,
thermal,
gravitational,
sound,
light,
elastic,
Electromagnetic,
Chemical energy,
Nuclear energy.
• The forms of energy are often named after a
related force.
Kinetic Energy:
• The energy of movement.
http://digital-photography-school.com/wp-content/uploads/2007/08/movement-blur-1.jpg
Potential energy
The stored energy of position.
http://www.solarpowerwindenergy.org/wp-content/uploads/2009/05/kineticandpotentialenergy.jpg
http://www.greenscreen.org/articles_sr/energy/images_potential_kinetic_energy/potential_kinetic.jpg
http://www.physicsclassroom.com/Class/energy/u5l1b1.gif
Thermal / Heat energy
http://www.physast.uga.edu/~rls/1020/ch4/fig4-4.jpg
This is the energy in the molecules of a substance which
move. More thermal energy means more molecule
movement – so it is really Kinetic energy on a molecular
scale!
Gravitational Energy
• This is a type of energy that an object has
because of its mass. The bigger an
object’s mass the greater its gravity.
http://www.phys.unsw.edu.au/~cgt/cgt/Honours_Projects_files/shapeimage_2.jpg
Sound energy
• The energy carried in waves in the air.
http://www.gobates.com/HM00050_.gif
Light energy.
• The energy carried in light waves. Nearly all life on this
planet depends on this as its original energy source.
http://farm1.static.flickr.com/75/227649503_88121cf734.jpg
Electrical energy
• The energy
carried by
moving
charges.
http://universalgeneral.com
/db4/00336/universalgener
al.com/_uimages/41k_Clou
dLightening.jpg
Elastic energy
• A type of potential energy.
http://www.bbc.co.uk/schools/gcsebitesize/science/images/energy_elastic.jpg
Electromagnetic energy
• Energy carried by electromagnetic waves.
Light energy is one type of these energies.
http://www.nasa.gov/centers/langley/images/content/114284main_EM_Spectrum500.jpg&imgrefurl=http://www.nasa.gov/centers/langley/science/FIRST_prt.htm
&usg=__VVUKc2-ReBx_iG9MsP9R6VXr_7s=&h=317&w=500&sz=67&hl=en&start=6&um=1&tbnid=6VN-zkKvE3H3M:&tbnh=82&tbnw=130&prev=/images%3Fq%3Delectromagnetic%2Benergy%26ndsp%3D18%26hl%3Den%26lr%3D%26um%3D1
Chemical energy
• The energy found in the bonds between
atoms.
http://www.chemistry.wustl.edu/~courses/genchem/LabTutorials/Cytochromes/images/fl
owchart1.jpg
Nuclear energy
• The energy found within an atom.
http://library.thinkquest.org/06aug/01200/Graphics/705px-Nuclear_fireball.jpg
Law of Conservation of energy
• Energy cannot be created or destroyed, it
can just change from one type to another.
• An energy changer is called a TRANSDUCER
How does this apply to living
things?
http://en.wikipedia.org/wiki/File:Energy_and_life.png
Think of a car.
What energy changes take place in a car?
http://www.foothill.edu/sustainability/smart-car.jpg
What about this one?
http://www.speedace.info/solar_cars/solar_car_images/auburn_univer
sity_solar_car_banked_road_test.jpg