Download Energy Flow Introduction

Energy diagrams show the flow of energy from one source to another. Energy cannot be created nor
destroyed, it just changes from one form to another. By showing the flow of energy, one can see how it
can be transformed. We can use these diagrams to show inputs and outputs as stated in the Washington
Science Standards(High School EALR 1- 9-12SYSB & EALR 4-9-11PS3A and Middle School EALR 1- 6-8
SYSC and EALR 4-6-8-PS3A &PS3E). The type of interaction occurring when light illuminates objects or
moves to your eye is called a light interaction. The type of energy transferred during a light interaction
is called light energy.
Interaction Type _______________________________________
Source
Receiver
Beginning enrgy Form
The Original Object
(The Sun, A Battery)
Energy Transfer
The Object Receiving
the Energy
(A plant, a ball, a
lightbulb)
Increasing Energy
Form (What Kind
of Energy is Now
Being Used?)
Decreasing Energy
Form (What type
of energy does the
original object
have?
Sample:
Battery
Decrease in
chemical
energy
Electrical Energy
Light Bulb
Increase in
light , heat
energy
Energy Is the Ability To Do Work
Energy comes in different forms:







Heat (thermal)
Light (radiant)
Motion (kinetic)
Electrical
Chemical
Nuclear energy
Gravitational
The Sun is the Ultimate Energy
Source
Most forms of energy actually
originate from the sun.
Energy is in everything. We use energy
for everything we do, from making a jump
shot to baking cookies to sending
astronauts into space. There are many
forms of energy. However, energy is not a physical thing: you can’t buy a box of energy.
Energy is simply the ability to produce a change.
There are two main types of energy:


Stored (potential) energy
Working (kinetic) energy
For example, the food you eat contains chemical energy, and your body stores this energy until
you use it when you work or play. The sun gives radiant energy to the plant which in turn
converts the radiant energy to chemical energy, a more usable form for animals to obtain the
energy they need to survive.
Radiant Energy
Plants absorb sun’s energy and convert it
to glucose (sugar), a type of chemical
energy.
Mouse nibbles on plant and
chemical energy passed on to it.
So indirectly, it obtains its energy
from the sun.
Potential Energy
Potential energy is stored energy and the energy of
position — gravitational energy. There are several
forms of potential energy.
Kinetic Energy
Kinetic energy is motion — of waves, molecules,
objects, substances, and objects.
Chemical Energy is energy stored in the bonds of
atoms and molecules. Biomass, petroleum, natural
gas, and coal are examples of stored chemical
energy. Chemical energy is converted to thermal
energy when we burn wood in a fireplace or burn
gasoline in a car's engine.
Mechanical Energy is energy stored in objects by
tension. Compressed springs and stretched rubber
bands are examples of stored mechanical energy.
Nuclear Energy is energy stored in the nucleus of
an atom — the energy that holds the nucleus
together. Very large amounts of energy can be
released when the nuclei are combined or split apart.
Nuclear power plants split the nuclei of uranium
atoms in a process called fission. The sun combines
the nuclei of hydrogen atoms in a process called
fusion.
Radiant Energy is electromagnetic energy that
travels in transverse waves. Radiant energy includes
visible light, x-rays, gamma rays and radio waves.
Light is one type of radiant energy. Sunshine is
radiant energy, which provides the fuel and warmth
that make life on Earth possible.
Thermal Energy, or heat, is the vibration and
movement of the atoms and molecules within
substances. As an object is heated up, its atoms and
molecules move and collide faster. Geothermal
energy is the thermal energy in the Earth.
Motion Energy is energy stored in the movement of
objects. The faster they move, the more energy is
stored. It takes energy to get an object moving, and
energy is released when an object slows down.
Wind is an example of motion energy. A dramatic
example of motion is a car crash, when the car
comes to a total stop and releases all its motion
energy at once in an uncontrolled instant.
Gravitational Energy is energy stored in an
object's height. The higher and heavier the object,
the more gravitational energy is stored. When you
ride a bicycle down a steep hill and pick up speed,
the gravitational energy is being converted to
motion energy. Hydropower is another example of Sound is the movement of energy through
gravitational energy, where the dam "piles" up water substances in longitudinal (compression/rarefaction)
from a river into a reservoir.
waves. Sound is produced when a force causes an
Electrical Energy is what is stored in a battery, and object or substance to vibrate — the energy is
transferred through the substance in a wave.
can be used to power a cell phone or start a car.
Typically, the energy in sound is far less than other
Electrical energy is delivered by tiny charged
particles called electrons, typically moving through forms of energy.
a wire. Lightning is an example of electrical energy
in nature, so powerful that it is not confined to a
wire.
Throwing a ball into the air is a good example of how kinetic and potential energy work. In this scenario,
there is a continuous change from kinetic energy to potential energy.
Imagine a ball lying on the ground without motion. At this point, both kinetic and potential energy are at
zero. When the ball is tossed into the air, there is a burst of kinetic energy. As the ball reaches its
maximum height, the kinetic energy gets smaller and smaller. Finally it becomes zero. Meanwhile, the
potential energy is increasing. As the ball reaches its maximum height, its velocity is zero. Now all the
energy in the process is saved as potential energy.
When the ball begins to fall down to the ground, the potential energy is once again gradually converted to
kinetic energy. Finally, the ball lands on the ground and becomes motionless.
In the final example below, a monkey finds an abundance of tasty stored solar energy in the carbohydrate
molecules of a banana. Though we don't show it in the diagram below, it is worth remembering that the
first energy conversion begins in the sun, where matter is converted to energy in a nuclear fusion reaction
during which Hydrogen atoms are changed into Helium atoms. A by-product of this process is
tremendous amounts of a type of energy called electromagnetic radiation (visible light, x-rays, ultraviolet
light, infrared, gamma-rays, micro-waves, and radio waves) that pours out of the sun into space . Some of
this former-matter-turned-into-energy falls on earth. Down here we call it solar energy.
Every cell in the monkey's body (and ours) is constantly converting the stored solar energy in glucose
into work and heat. The work is used to carry on cell processes like growing, reproducing, moving
molecules around, and getting rid of waste. The heat is a byproduct of the fuel "burning" process. Heat is
always given off when fuel is burned, whether it is in a diesel engine or an animal cell. In an animal the
heat can be used to help keep its body at a certain warm temperature. Sometimes our bodies make too
much heat (especially if we are dancing to loud music) and we have to do things like sweat or pant (if we
are dogs) or fan our big heat exchanger ears (if we are elephants) to try to cool down.
All of the heat flows eventually into the surrounding air. The quantity of total energy has not, and will
not, change. It has just moved to different forms and different places.
Energy Transfer Activity Sheet
Use the Energy Transfer Diagrams below to illustrate the transfer of energy through your identified
system. In many cases you will need to connect a chain of transfer diagrams to fully illustrate the
energy transfer through the entire system.
Energy Source
Energy Receiver
Energy Transfer
Decrease In
Increase In
You can connect the energy transfer diagrams to more fully show the flow through the system.. Focus
on the energy originally used and the form it now takes.
Decrease in
Increase in