Energy - pams-piper

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Transcript Energy - pams-piper

Energy
Looney Tune Energy?...
Energy
 Energy - the
ability to do
work
 Measured in
joules
 There are 5
MAIN types
Forms of Energy





Mechanical
Heat
Chemical
Electromagnetic
Nuclear
Nuclear
Mechanical
Heat
Chemical
Electromagnetic
Mechanical Energy
 The energy that
is associated
with motion
Know these examples!
Heat Energy
 The internal motion of atoms.
 The faster the particles move, the hotter
they get.
 Results from friction.
DO NOT WRITE!
Friction is producing heat between
the saw and the wood. Turning
mechanical energy into
heat energy.
Chemical Energy
 Exists in the bonds that hold atoms
together.
 Examples: burning fuel or when our
body uses food.
Electromagnetic
Energy
 Moving electric
charges (electricity)
 Examples:
 Light,
 X-rays
 Radio waves
Nuclear Energy
 The nucleus is a source of
energy
 Fusion and Fission
The types of energy…
Potential and Kinetic
Energy
 Each of the five forms of
energy can be classified
as either potential or
kinetic energy
 Potential energy is
stored or energy of
position
 Kinetic energy is the
energy of motion
Kinetic Energy
 The faster an object moves the more
kinetic energy it has
 Kinetic energy depends on mass and
velocity (speed)
Calculation K.E.
 Who has more kinetic
energy, an 80 kg man
moving at 4 m/sec or a 40
kg boy moving at 8 m/sec?
K.E. = 80kg x 4m/sec2 = 640 j
2
K.E. = 40 kg x 8 m/sec2 = 1,280 j
2
Potential Energy
 An object stores the energy.
 Can be based on position
like a stretched rubber band,
a wound-up watch, anything
held up high…
 Can be stored in a battery
as chemical, in fuel until it is
burned, stored in the
nucleus until it is split
Gravitational Potential
Energy
 Potential energy that is dependent on
height. Example: waterfall, falling
snowflake.
 The higher up an object is the more
G.P.E. it has.
 The more mass, the more G.P.E.
G.P.E. = weight x height
Potential and Kinetic
Energy
Energy Conversions
*take your own notes here!
 All energy types can be changed
from one form into another.
 Electric motor is electromagnetic
to mechanical
 Battery is chemical to
electromagnetic
 Sun is nuclear to electromagnetic
to heat
 What other form of energy can
the sun’s energy be converted
to? Hint: flowers
Energy
Conversions
 The most common energy conversion
involves the changing of potential energy
to kinetic energy or kinetic energy to
potential energy
Ball slows down
Ball speeds up
Nuclear Power Plant
Example
Conservation of
Energy
 The Law of Conservation of Energy states that
energy can be neither created nor destroyed
by ordinary means
 Albert Einstein’s Theory of Relativity states that
mass and energy are directly related, energy
and mass are interchangeable
 In other words: the smaller something is the
more energy it creates. Example: the atom
Physics principles:
 A force is required to change the motion
of an object. Changes the energy of
every object.
 Motion is faster when more energy is
used.
 Power is the rate at which work is done
and the rate at which energy is
consumed.
In conclusion…
This is just the
beginning of Physics!!! I
know you’re excited!