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Friction Drag Racing
The Classical Theory of Static and Kinetic Friction a Why There’s So Much Confusion
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Who is this man?• His salary is over $50M per year• His total income estimated at $100M per
year• He is one of the best known athletes in the
world (outside of the US) • He is one of the most highly conditioned
atheletes in the world• He recently won an unprecedented sixth
World Championship• He has won over 60 individual
championship events• He has his own fleet of private jets and his
own airport• A team of approximately 800 scientists,
engineers, mechanics and support personnel are employed soley to support his efforts
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What does that HAVE to do with physics?
• The Physics lets him do this…
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And if he gets it wrong…
• Why are these concepts important to him?
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unit
• Where it fits
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Concepts
• Empirical vs theoretical• Standards• Theme
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review
• Previously covered material• what you are going to see (DO,
LEARN)
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assessment
• Show Video• QUESTIONS AFTER VIDEO CLIPS
• what makes the cars move?• what makes them stop?• what makes them turn?
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THEORY
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History
• da vinci• Coulumb• Amonton
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Standard model
• Assumptions• validity• flaws• reality
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methods
• average acceleration• friction vs gravity
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calculations
• CALCULATORS
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activity
• Materials• Roles• Cars• Stopwatches• Protractors• Calulator
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Rules
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sample calculations• Elapsed time• Average velocity• Average acceleration
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discussion
• what you saw• standard model
• Assumptions• When is it valid?• When does it break down?• What good is it?
• Other models• Rolling• deformation
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Factors BOC
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Potential Errors
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the real world
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Things Impacted by these concepts
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Jobs
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Sports
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Around the house• History• Technology• Language• Politics• Health
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Sciences
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food for thought• Examples where standard model doesn’t fit• Questions for consideration
• Is there friction in a vacuum?• What would happen if the two surfaces were made out of material that
repelled each other?• Is there friction when the two materials are inert and have no attraction or
repulsion to each other?• Why would a thin sheet act as though there is a vacuum acting on it?• When an object moves through a fluid do the molecules in direct contact
with the surface move?• Wind resistance is often characterized as the friction produced when an
object moves through a gas (air) which acts in a direction opposite to the motion of the object. Is the heat produced by the moving object created
• directly (by air molecules directly in contact with the surface of the object)moving across molecules of the surface of the object)
• indirectly by the motion of air molecules relation to each other
• relevance • next topics
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references
• Books• WEB sites
• www.hyperphysics.com
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Resources
• drawings• ramp• cars• weights
• Measurement equipment• stopwatch• protractor• tape/rule• scale
• Worksheets
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appendices
• ideas for other activities• history
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Introduction
• Subject: Secondary Physics• Unit: Newtonian Mechanics• Principle: Kinetic Friction