Download Unit 1: Energy

ENERGY
What is it?
Energy Unit
Energy
Gives an object the ability to move or do work.
The ability to cause a change.
The Law of Conservation of Energy -Energy can not be
created or destroyed but can be converted from one form to
another.
Types of Energy
Name
Definition
Potential
Energy
stored energy: has the
ability to do or cause
change or motion but is
not at that time.
Energy of position
Gravitational
Potential
Energy
(GPE)
Formula
GPE = mgh,
m = mass,
g = 9.8 m/sec2 ,
h = height
GPE = (wt)h
wt = mg
Chemical
the arrangement of the
Composition/ atomic structure
Elasticity
Kinetic
Energy
energy of motion or work.
Forms of Energy
KE = 0.5mv2 ,
m = mass,
v = velocity
Name
Definition
Mechanical
Energy
Energy involving the
motion of matter.
Heat/Thermal
Energy
The internal motion of
the atoms.
Electromagnetic The motion of
Energy
charged particles.
Example
sound, wind,
water falling over
a waterfalls,
riding a bike,
hitting a ball
these are a few
.
electricity, light,
x-rays,
microwaves,
This energy can travel radio waves,
through space.
ultraviolet.
Chemical
Energy
The energy that exist
in the bonds that
hold the atoms of
compounds together.
This energy is
released when these
bonds are broken.
Nuclear Energy Energy from the
nucleus of the atom.
This energy can be
released when the
nucleus is split into 2
smaller nuclei this is
called fission.
This energy can also
be released when 2
smaller nuclei are
combined into a large
nucleus this is called
fusion.
Energy Conversions
the changing of energy from one type or form into another.
This can between potential and kinetic or between any two
or more of the 5 forms of energies.
During conversions energy is lost or changed into a form that
is less usable.
Energy Efficiency
the measurement of how much of the energy that was
started with is changed into less usable form or how much
usable energy there is left after the conversion.
Nonrenewable vs. Renewable Energies
Name
Definition
Nonrenewable energies that cannot be
replenished. Once they are
used up there is no more of
them.
Renewable
Example
oil, coal,
natural gas,
gasoline
energies that can be
wind, solar,
replenished. These
hydro, geoenergies are often called
thermal, tidal
green energies. That is
because they are
environmentally friendly. This
means causing little or no
pollution and will not run out.
These are all so called
alternative sources of energy.
Heat Energy
Energy that is caused by internal motion of the particles of
matter.
A form of Kinetic Energy
Particles – atoms or molecules that make up matter.
Temperature
The measurement of the amount of Heat Energy.
the average Kinetic Energy of the particles of a given piece
of Matter.
Scales used to measure Heat Energy
Fahrenheit most commonly used in the US, developed in
the 1700’s
Celsius
Used in the rest of the world, developed in
1740’s
Kelvin
Absolute zero O0K is -2730C
Calorie
The amount of heat energy needed to rise 1g of water 10C.
Food Calorie or diet calorie is the same as a kilocalorie.
1 calorie = 4.18 joules
Specific Heat
The amount of heat energy need to rise 1g of a Substance
10C.
Specific Heat of water is 1 , iron is 0.11 (see pg 436)
Heat Energy Transfer:
Name
Definition
Conduction Heat Energy is transferred from one object to
another by direct contact.
Conductors – matter that transfers energy
easily.
Low Specific Heat
Insulators – energy is transfer poorly or not at
all.
High Specific Heat
Convection Heat Energy is transferred by currents in fluids.
Currents are movement of particles within a
fluid.
A Fluid is a gas or liquid.
Radiation
Heat Energy that is transferred through
Electromagnetic waves.
This type of transfer can travel through empty
space.