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Physics of sports Wed, Sep 26, 2007
If I ever become a teacher (which I won't), I'll teach physics.  But I'll teach it better than it was taught to me (that's right, Ms. C.) by comparing everything to sports.  I know the world isn't full of athletes, but I also know that physics classrooms aren't full of physicists. 

Position/Velocity
Q:  If Roger Clemens throws a 97-mph fastball, how long will it take to reach the head of a soon-to-be-angry batter? 
A:  If the pitcher's mound is 60'-6" from home plate, an object traveling at 97 mph will take
(1 hour/97 miles) * (3600 seconds/1 hour) * (60.5 feet) * (1 mile/5280 feet) = 0.425 seconds
(This is an approximation because the ball loses velocity as it travels through the air and it falls farther to the ground as it approaches the batter.  But for high school physics, it's good enough.)

Impulse/Momentum
Q:  If a 250-lb Jeremy Shockey catches a pass during a Giants game while running 8 mph and collides with a 180-lb defensive back running 10 mph, who will have the bigger headache? 
A:  momentum = mass * velocity
Shockey's momentum = 250 * 8 = 2000 lb-mi/hr
DB's momentum = 180 * 10 = 1800 lb-mi/hr
Even though the defensive back is running faster, his inferior weight will cause him to be a part of the post-game highlight reel. 

Trajectory
Q:  What angle must a hibachi chef fling a piece of chicken to get it into the mouth of a person sitting 5 feet away if the chicken's initial velocity is 13 feet/second, assuming the chicken's starting vertical location is equal to the vertical location of the person's mouth?  (Ok, this isn't quite a sport, but it's close enough.)
A:  angle = 0.5 * arcsin(gravitational acceleration * range / velocity2) = 0.5*arcsin(32.2*5/132) = 36.2 degrees
If his aim is even one degree off, expect to catch it with your eyeball. #math