Lab Safety Policies
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Don’t stand on lab chairs
Don’t sit or stand on lab
tables
No dangling jewelry or
loose clothes.
No open toed shoes.
Be careful with sharp
corners.
Recall location of phone
and first-aid kit.
Report ALL injuries
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Engineering 1182 Lab Overview
Team Design/Build Project
Details are in your course packet: read them and
make sure you understand!
Roller Coaster
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Design
Documentation
Building
Testing
Report
Presentation
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Overview of Labs
Lab 1
Introduction to Roller Coaster Design
Lab 2
Roller Coaster Energy Losses
Lab 3
Roller Coaster Circuits with Circuit Prototyping
Lab 4
Roller Coaster Speed Sensor Calibration
Lab 5
RC Building Session #1
Lab 6
RC Building Session #2
Lab 7
RC Building Session #3
Lab 8
RC Final Construction - Preliminary Testing of Design
Lab 9
RC Final Testing of Design
Lab 10
RC Oral Presentations
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Engineering 1182:
Roller Coaster Dynamics-1:
Energy Conservation
Physics Concept - Energy
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ENERGY is a conserved property of an object that
relates to its ability to do work. Energy can have
a number of forms, for example mechanical,
electrical, chemical, or nuclear. E
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Units: Joules or N-m (Newton-meter).
There are different formulas describing different
forms of energy.
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Law of Conservation of Energy (COE)
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Energy can neither be created nor
destroyed.
Energy can only be changed from one
form to another.
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Forms of Energy in a Rolling Ball
Energy of the Ball
Potential Energy (PE)
Kinetic Energy (KE)
Total Mechanical Energy of the ball = PE + KE
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Kinetic Energy in a Rolling Ball
Kinetic Energy (KE)
Translational Kinetic
Energy (TKE)
Rotational Kinetic Energy
(RKE)
Kinetic Energy of the ball = TKE + RKE
A rolling ball has both forms of Energy!
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Translational Kinetic Energy
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An object has Translational Kinetic Energy (TKE)
when it is undergoing linear displacement
TKE = ½mv2
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m = mass of object
v = velocity of object
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Rotational Kinetic Energy (RKE)
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An object spinning about an axis is said to
have Rotational Kinetic Energy.
RKE = ½Iω2
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I: Moment of Inertia
ω: Angular Velocity (radians/sec)
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Moment of Inertia (I)
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The moment of Inertia (I) of
an object
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Measures the resistance an object has
to rotating about a particular axis,
similar to the way that mass is the
object’s resistance to changing its
velocity.
Depends on its mass, shape and axis
of rotation.
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Angular Velocity (ω) vs Linear Velocity (V )
Linear Velocity (V ) 
Change in Linear Displaceme nt ( Meters)
Time( Seconds)
Angular Velocity ( ) 
Change in Anglular Displaceme nt ( Radians )
Time( Seconds)
ω
R
v
V  R
This relationship between linear and angular
velocities holds if and only if the ball is not slipping
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Effective Rolling Radius
Rails
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R’
The ball sits down between the tracks
making the rolling radius smaller.
The angular velocity is increased.
If the rails are not supported and split
further apart, the ball will sit farther down.
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Energy Transfers
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As the ball rolls down the roller coaster
track, some energy of the moving ball is:
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Lost to friction and dissipated as heat
Spent in overcoming Air Resistance
Lost to Structural Deformation
Converted to Sound Energy
Unwanted
Energy
Losses !
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Energy Transfers (continued)
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In general, energy transferred away from
the ball will NOT come back, and so the
total mechanical energy of the ball
will be always decreasing.
In the real world, we cannot avoid losses
but can only MINIMIZE and/or ALLOW for
them.
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Let’s put it together !
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For the ball rolling along the roller coaster
track, between any two subsequent points:
PE1+ TKE 1+ RKE1
= PE2 + TKE2 + RKE2 + “Energy Losses”
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Design Considerations
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You will be estimating the velocity of the
ball at selected points along your roller
coaster track using energy calculations to:
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Make sure the velocity into turns is not too
high (making banking difficult)
Make sure that the ball can reach the top of
vertical loops
Make sure that the ball will not fly off the top
of bumps
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Assignments and Reminders
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Lab Memo (Team)
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