Download Potential and Kinetic Energy

Potential and Kinetic Energy
What is Energy?
• The ability to cause change
Energy notes entry # 4 11/5
Potential
Energy
Definitions
Dependent
on…
Examples
Forms of
Kinetic
Energy
Potential Energy
Definition
• Potential Energy is stored
energy. It is not energy in
motion.
• Potential energy is
dependent on its position
(location) and its condition
(new battery vs. used
battery.)
•
•
•
•
•
Examples
Batteries
Gasoline
Food
Plant on a windowsill
Acorn hanging on a tree
POTENTIAL ENERGY
• Things have energy depending on where they are
(position/ location).
The penny has LOTS of potential
energy; the rock doesn’t.
penny
rock
Empire State
Building
flowers
Common Uses
• Potential energy is stored energy so it is used
to “run” many things for example
– Gasoline “runs” cars
– Batteries “run” our
toys
Common Uses
• Food is our potential energy and it helps us
survive and do activities.
FORMS OF POTENTIAL ENERGY
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•
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Chemical (food, gasoline)
Nuclear (fusion & fission)
Gravitational (position or place)
Stored Mechanical (stretched rubber band)
Understanding Check
• Tell the person next to you: Why do these people
have potential energy?
Choose one of the following sentence frames. Using
your science journal, fill in the blanks using what you
know about potential energy.
• ___________ can be described as
________________.
• Characteristics (components) of
_____________include _______________ and
__________________.
• __________ is widely acknowledged as
___________ and exhibits
_______________________.
Please grab your science journals!
Kinetic Energy
Definition
• Energy in the form of
motion
• Kinetic energy is dependent
on mass and speed. The
greater the mass and speed
the more kinetic energy the
object has
Examples
• Person running
• Bicycle wheel spinning
• Frisbee flying in the air
KINETIC ENERGY
Things have energy depending on how fast they move.
Which has more kinetic energy?
FORMS OF KINETIC ENERGY
• Sound
– Travels in waves, JUST LIKE IN THE OCEAN
– Has to have something to travel through.
Energy traveling through AIR
FORMS OF KINETIC ENERGY
• Radiant
– Also travels in waves
– DOESN’T need anything to travel through
Earth
Sun
Energy traveling through SPACE
FORMS OF KINETIC ENERGY
• Electrical
– When electrons move.
– lightning and electricity are kinetic
energy.
EXAMPLES OF KINETIC ENERGY
Sound
Light
Dancing
Electricity
Understanding Check
• Tell the person next to you: How do you know he
has kinetic energy?
Choose one of the following sentence frames. Using
your science journal, fill in the blanks using what you
know about kinetic energy.
• One example of ____________ is
______________.
• Characteristics (components) of
_____________include _______________
and __________________.
• Frequently associated with _________,
___________ is understood as
____________.
Comparing and Contrasting Potential
and Kinetic Energy
• There are many different types of energy. The
two main types of energy are potential and
kinetic energy.
• How are these two types of energy alike
(compare) and how are they different
(contrast)?
Use one of the following types of graphic organizers to
compare and contrast Potential energy and Kinetic
energy
Potential
Alike
Kinetic
Alike
Different
Different
Potential
Kinetic
When you are done with your graphic organizer,
answer the following questions on a separate sheet of
paper to be turned into me as your ticket out the door
1. Use and example (not given in the
PowerPoint presentation) to explain how
potential energy can transform into kinetic
energy.
2. Why is understanding potential energy and
kinetic energy important to understanding
motion (movement)?
ENERGY DAY 2
Warm up
• Today we are going to warm up with a few science
demonstrations (and short play time)
• Please set up your science journals with the following data
table (using a ruler is optional)
Activity
Poppers
Ping Pong poppers
Rattle backs
Gyro rings
Astroblaster
When does it have
potential energy?
When does it have
kinetic energy?
Button Whizzer lab
• Learning target: to observe how potential and
kinetic energy can be transferred, stored and
released
ENERGY DAY 3
Warm up
Law of conservation of energy
• Energy is neither created nor destroyed. It
just changes from one form to another. You
always have the same amount of energy in a
system. No more no less!
What does this really mean?
• New concept: Law of Conservation of energy
• Example Sentence:
Definitions:
Essential characteristics
.
.
.
.
Examples:
.
diagrams
.
.
.
.
.
.
.
Conservation of Energy
• This means that kinetic energy can turn into
potential energy which can turn into kinetic energy which
can turn into potential energy which can turn into kinetic energy
which can turn into potential energy
which can turn into kinetic energy which can turn into potential energy……..
Kinetic
Potential
CONVERSION
From http://www.eia.doe.gov/kids/energyfacts/science/formsofenergy.html
LAVA LAMP
LAVA LAMP
Kinetic: Electricity, Light, Heat, Motion
KE: Motion
KE: Light
KE: Heat
KE: Heat
Potential: stored energy in the wax, which
isn’t transformed.
KE: Electricity
Energy Flow
1. Kinetic energy in the form of electricity enters the lamp
through the outlet and cord.
2. A bulb turns this electricity into another form of kinetic
energy: light. The light flows into the room.
3. This light also creates heat, yet another form of kinetic
energy.
4. The heat flows into the room, and also melts the wax
inside the lamp, making it move.
5. The same amount of energy that went into the lamp
comes out of the lamp in 3 different forms: light, heat, and
motion.
Energy Flow
Electricity
Light
Heat
Motion
THE
ROOM
LAVA LAMP
Energy Flow
Electricity
Light
KE: Motion
KE: Heat
Heat
KE: Light
KE: Heat
Motion
KE: Electricity
THE
ROOM
Consider:
The yo-yo.
The Yo-Yo
PE: height, string
PE: height, string
PE: height, string
PE: height, string
KE: motion
KE: motion
KE: motion
Potential: height, wound string
Kinetic: yo-yo falling & rising
Energy Flow
Height
Wound String
Motion
Energy Flow
1. The Yo-Yo has only potential energy at the beginning.
There are two kinds: potential energy because of height, and
the wound string.
2. As the yo-yo drops, the potential energy is transformed
into the kinetic energy of the yo-yo moving.
3. When it is halfway down, the yo-yo has the same amount
of potential and kinetic energy.
4. When the yo-yo gets to the bottom all the potential energy
has turned into kinetic energy.
5. As the yo-yo comes back up the string the process is
reversed. Kinetic energy is transformed back into potential
energy (the wound string, and height).
Let’s practice together
1. What types of energy?
2. How does energy flow?
3. Concept map of energy
flow.
4. Describe the flow of
energy.
1. Kinetic energy, Chemical Potential energy, thermal
energy, light (radiant) energy, electrical energy
2. Kinetic (motion), chemical potential (batteries),
electrical (wires connecting to light) thermal(from
light and wires), light (given off into the room)
3. KE CPE electrical thermal light
The Room
Can we fill more of this in?
• New concept: Law of Conservation of energy
Definitions:
Essential characteristics
.
.
.
.
Examples:
.
Diagrams
.
.
.
.
.
.
.
Energy Flow
1. Pick an object and sketch it
2. Identify the types of energy that your object uses.
3. Draw arrows on your object to show the flow of energy.
4. Make a chart/concept map of the energy flow.
5. Write a SHORT paragraph describing the energy flow. How
does this show that energy isn’t created or destroyed, it just
changes?
ENERGY DAY 4
Thermal Energy
• We call this heat.
• Actually the internal energy in substances .
• As molecules and atoms within substances
move around this is what causes thermal
energy.
• The faster the movement, the greater the
amount of thermal energy.
Hard to understand?
• Think about when you
are running, what
happens the more you
move?
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Muscles move
Start to sweat
Temperature increases
Basically you are
converting kinetic
energy (motion) into
thermal energy (heat)
by moving the
molecules that make up
your body
Other Examples of Thermal Energy (Heat)
•
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Geothermal energy
Friction
Stoves/ ovens
Fire
Quick Demonstration
• Rub your hands together
– What do you notice?
• Move faster and then slow down
– Do you notice a difference?
Choose one of the following sentence frames. Using
your science journal, fill in the blanks using what you
know about thermal energy.
• When ___________ is added,
___________increases.
• ________ has been caused by _______, thus
__________.
• _______ has/have caused _______. Which, in
turn, results/resulted in____________.
How does Heat Travel
• Heat always transferred from hot items to cold
items.
• Hot soup
refrigerator
• Hot spoon
ice cream
• Warm soda
Ice cubes
Remember the hotter something is, the faster the
molecules and atoms are moving which means
more energy. This energy overcomes the cooler
things that have less energy. It transfers energy
into them which heats them up.
Demonstrations
• Place one hand on the table- what do you
feel?
– Your hand is transferring heat from your hand to
the table.
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Ring and ball (demo)
Hand boilers
Fortune fish
Thermo boards
Conservation of energy lab