Transcript Physics of Sports 2005

The Physics of
Sports
Physics
explains
things that
are very,
very small.
Physics explains things that are
very, very large.
Physics explains things that are
right in front of us.
Newton’s First Law
• Objects at rest remain at rest
• Objects in motion remain in motion
UNTIL YOU APPLY A FORCE
Newton’s Second Law
F = ma
What forces are important in sports?
Flight Path
The Home Run Swing
• Ball arrives on 100 downward trajectory
• Andre Dawson and Frank Thomas swing up at 250
• Ball takes off at 350
The optimum home run angle!
Courtesy of A. Nathan, University of Illinois. http://www.npl.uiuc.edu/~a-nathan/pob/
Newton’s Third Law
For every action there is an equal and
opposite reaction.
Conservation of Energy
Potential Energy
Kinetic Energy
Kinetic Energy
Compression Energy
Heat and Sound Energy
Conservation of Momentum
If m1 = m2 , then v1 = v2
Equipment features
• Ball material, size, shape, and texture
• Properties of the club, bat, racquet, or stick
How fast
can you
throw a
ball?
Momentum transferred
Energy stored and released
David Rawlings, PGA Golf Professional
http://golflessonslondon.wordpress.com/
Hockey Slap Shot
Pole Vault
Progress
http://ffden-2.phys.uaf.edu/211_fall2002.web.dir/Daniel_Lenord/vault.html
Air Resistance (drag)
F
R
I
C
T
I
O
N
Resistance & Friction
The Power of Spin
Spins in Figure Skating
Reaction Time
Downhill skier speed: 80 mph
Reaction Time in Baseball
Courtesy of R. Adair through A. Nathan.
Measure your reaction time…
Compare your reaction time…
Equation used: t = √((2d)/g)
Physical laws explain the world
• Newton’s Laws of Motion
• Conservation of Energy
• Conservation of Momentum
These laws help us explain everything
about sports, but there is more to learn.
Physics really is everywhere!
Visit Fermilab
www.fnal.gov
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Buffalo viewing
Bicycling
Walking
Roller blading
Canoeing
Fishing
Visit Fermilab
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On-line activities:
ed.fnal.gov
Lederman Science Center
Tours
Saturday morning physics
Ask a Scientist
The Physics of
Sports