Transcript Training - Powerpoint

Roller Coaster
Vanderbilt Student Volunteers for Science
Training Presentation
Fall 2004
Important!!!!
• Please use this resource to reinforce your
understanding of the lesson! Make sure you
have read and understand the entire lesson prior
to picking up the kit!
• We recommend that you work through the kit
with your team prior to going into the classroom.
• This presentation does not contain the entire
lesson—only selected experiments that may be
difficult to visualize and/or understand.
I. Introduction (Optional)
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Please see manual for detailed explanations.
The Law of Conservation of Energy states that:
– Energy can be neither created nor destroyed by ordinary means.
– Energy can only be converted from one form to another.
– There are five forms of energy: mechanical, heat, chemical, electromagnetic,
and nuclear.
– There are two states of energy: kinetic and potential.
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All five forms of energy can be classified into either one of these states of
energy (kinetic or potential).
How Does a Roller Coaster Work?
The ride often begins as a chain and motor or other mechanical device)
exerts a force on the train of cars to lift the train to the top of a very tall hill.
Once the cars are lifted to the top of the hill, gravity takes over and the
remainder of the ride is an experience of the physics of energy
transformation.
The conversion of potential energy to kinetic energy is what drives the
roller coaster, and all of the kinetic energy you need for the ride is
present once the coaster descends the first hill.
II. Demo: Gravitational Potential Energy
Conversion to Kinetic Energy
• Have 1 or 2 VSVS members
hold the track so that it forms a
U shape. Hold it in the air so
that all students can see.
• Ask students to predict what
will happen to the speed of the
car as it rolls through the Ushaped track.
• Release the car. All students
should observe what happens
to the speed of the car.
II. Demo: Gravitational Potential Energy
Conversion to Kinetic Energy
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Draw a U shape on the board.
Ask students the following questions:
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Where was the car traveling at the
fastest speed? (at the bottom of the U)
Where was the car traveling at the
slowest speed? (at the tops of the U)
Where does the car have the most
kinetic energy? (at the bottom of the U)
Where does the car have the least
kinetic energy? (at the tops of the U)
Where does the car have the most
potential energy? (at the tops of the U)
Where does the car have the least
potential energy? (at the bottom of the
U)
Put these results on the U-shaped
diagram on the board (as shown on
the right).
IV. Potential Energy and Roller Coasters
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Divide students into groups of three or
four (No more than 8 groups.)
Give each group a set of materials and
an observation sheet.
Tell them to design a roller coaster
with the following specifications:
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The first hill (the starting point) has to
be at a height of 4 feet.
There must be at least two more hills
after the first hill.
The BB must complete the journey
without any assistance from the group.
Tell students to tape or hold the
styrofoam cup at the end of the tubing
to catch the BB.
The tubing for the roller coaster can be
taped or draped across various items
in the room (desks, tables, walls, etc.).
The group that creates a roller coaster
with the most total inches of height in
the three hills wins the contest.
A successful roller coaster is one in
which the BB travels from beginning to
end without getting stuck in the tube.
IV. Potential Energy and Roller Coasters
• Answer the following
questions:
– A. What things affected
whether your roller coaster
worked or not?
– B. What happened when you
made a steep hill?
– C. Where did the BB have the
most potential energy?
– D. Where did the BB have the
most kinetic energy?
– E. What happened to the
potential energy as the BB
went from the top of the hill to
the bottom of the hill?
– F. Using the roller coaster as
an example, put in your own
words what "conservation of
energy"means.