Download Forms of ENERGY

Forms of
ENERGY
B2.1
Chemical Energy
• Chemical energy is the potential
energy stored in the chemical bonds
of compounds
Examples:
• Food provides energy after the bonds
found in food are broken
• The chemical energy in a match is
released after is it struck
Electrical Energy
• Electrical energy is the work done by
moving charges
– Can produce both heat and light
Examples:
• Light bulb
• Batteries
Magnetism
• Magnetism is a property, possessed
by certain materials, to attract or
repel similar materials. Magnetism is
associated with moving electricity.
Hans Oersted
• Discovered that electricity could
produce magnetism
• By placing a metal wire with a
current passing through it over a
compass, he noticed that the
compass wire moved.
• See page 166, Figure B2.3
Michael Faraday
• Discovered that magnetism could
produce electricity.
• By moving a magnet through a coil
of wire, Faraday produced an
electrical current and the first
generator
• See page 166, Figure B2.4
Nuclear Energy
• Nuclear energy is the potential
energy stored in the nucleus of an
atom. When the nuclei is split
(fission) or when two nuclei combine
(fusion) energy is released.
Solar Energy
• Solar energy is produced from a
hydrogen-hydrogen nuclear fusion
reaction with the release of nuclear
energy.
• Solar energy is often converted to
other forms of energy such as heat.
For example, a greenhouse.
Kinetic Energy
• Kinetic energy is energy that can do
work due to motion
• Examples include flowing water and
wind
Gravitational Potential
Energy
• Gravitational potential energy is
energy that has the potential to do
work due to it’s position above the
earths surface.
Example: A rollercoaster on top of a
crest
Mechanical Energy
• Mechanical energy is the sum of the
energy of motion and position
I.e. Mechanical energy =
kinetic energy + potential energy
Watch video: Two
forms of energy
Newton's cradle
• The motion of Newton's cradle was first
explained by a living force- “vis visa”
• What is actually happening is that the
gravitational potential energy of the raised
ball is converted into kinetic energy when
released. As a result, a majority of the
mechanical energy is conserved and the
cradle will continue this motion for some
time.
Heat Energy
• Heat energy is the transfer of
thermal energy due to vibrations and
the movement of atoms from a hot
object to a cold object
Joules Experiments
• Joules experiments supported the
idea that transformations of heat
energy into mechanical energy could
only occur when thermal energy
flowed from hot to cold objects. Also,
they also supported the idea that in
this process some energy, in the
form of heat, is always lost.
Joules Churn
As the mass falls, the water is
churned, causing the
temperature of the water to
increase.
The potential energy of the
mass is converted into the
kinetic energy of the paddles,
allowing the water to move and
transform into heat.
As a result, Joules experiment supported a connection between
potential energy and heat.
Falling Block Experiment
A falling block of wood hits a
stationary block and the temperature
of the block increases
The kinetic energy of the falling block
is transferred to the stationary block
and the temperature of the stationary
block increases as a result.
As a result, Joules experiment supported a connection between
kinetic energy and heat.
HOMEWORK
• Read pages 164 -170