The Top Ten Times You See Physics In Football

"Down! Set...........  Hut!" The center snaps the ball and he and the other linemen take steps back to set up in cup pass protection. The center has great confidence that he will be able to block the blitzing linebacker that is shooting A gap.  This is because the center knows that he is much larger than the linebacker, and he also knows that an object at rest will stay at rest and an object in motion will stay in motion according to Newton;s first law.
 The QB now has the ball, he pushes off and begins to back peddle. But while he is doing so he thinks about how the only reason is is able to move is because he is pushing on the ground in one direction while the ground is pushing him back in the opposite direction.  This reminds him of Newton's third law which says that for every action there is an equal and opposite reaction.   Before he plants his feet and sets up to throw, the QB remembers how the vectors were used in his physics class to show the direction and forces during the cart and Buggy example.
                                                            
 The QB has set up, selected his target, and begins his throwing motion.  His arm extends up and out reaching nearly full extension.  He knows that if he wants to throw the ball far it will require a great force.  And one way to get a larger force is a greater velocity.  So by extending out his arm, the QB places the ball further from the axis of rotation (his shoulder).
By placing the ball further from the axis of rotation, it must have a greater tangential velocity in order to maintain the same rotational velocity.  What this results in is that the ball comes off of his hand with a high velocity and force that will propel the ball to its target.

As the QB releases the ball and watches it fly ever so gracefully through the air, he cannot help but to look up at the stadium lights and appreciate the physics that make night games possible.  He thinks back once more to that same physics class he had in high school where he learned about circuits and electricity.  He makes the assumption that the stadium lights are rigged up in a parallel circuit because some of the lights are on, while others are burnt out or turned off. He knows that a circuit must be complete in order for a current to flow, and is considering how a series circuit is inferior to a parallel because an entire series circuit will fail if there is any breakage at any point.  And at that moment his ribs experience some breakage as he is blindsided by the blitzing linebacker that the center was supposed to have picked up.
The ball is now flying through the air on its way towards the receiver.  (They say that the ball has a mind of its own, and this one happened to have a high school level understanding of physics concepts...)  As it is flying through the air it begins to realize that it is slowing down.   Thankfully the ball does not panic because it understands what is happening to it.  The ball is slowing down because it is experiencing air resistance.  And the ball knows that air resistance is determined by two factors, speed and surface area.  The ball can rest assured knowing that it has not gotten fatter, it has simply been going fast and so it was experiencing increased air resistance  causing it to slow down.
The receiver has just made his break on the ball and is preparing to catch the ball.   So naturally he thinks about how if he wants to decrease the force acting on the ball therefore catching it softer, he must increase the time it takes to come to a  stop in his hand.   The receiver understands that  p=mv  and he also understands that (delta)p=J and that to find (delta)p, you take p final- p initial.  Since J=F(delta)t  he increase the time that the ball is in contact with his hand in order to decrease the force.
The receiver has successfully caught the ball and turns his head to prepare to juke.  He sees that the safety is breaking down and is about to hit him.  The receiver then prepares for impact.  He bends his knees in order to lower his center of gravity and places his feet shoulder width apart in order to widen his base of support.  Because the receiver lowered his center of gravity and widened his base of support he was very difficult to push over and so was able to shrug of the tackle.
 There is now only one thing stopping the receiver from the end zone, a help side corner is running in really fast.  The receiver knows that he cant outrun the corner, but he knows how he can use his speed against him.  Right before the corner is about to lay a big hit on  him, the receiver stops in his tracks and the corner goes flying past him.  The receiver knows that this is because the corners inertia kept him moving in his current state and resisted change in motion such as the receivers sudden stop.
Touchdown!! Everyone goes crazy! Well except for the guy carrying his drink up the stairs in the top tier bleachers, he missed it cause he was busy doing work.  As he was walking up the stairs he was was doing work on his drink as he was moving with a force and a distance that was parallel.  
All the players are loading the bus after the win and get ready to drive back.   The punter who happened to be a physics minor in college thinks its pretty cool how the motor in the bus or any other motor is really nothing more than just a current carrying wire that is experiencing a force in its magnetic field causing a torque and making it rotate.