Football is a form of play consisting of a variety of different physics topics within the game. These topics include momentum, energy, forces along with acceleration and projectile motion.
In terms of momentum, football requires the biggest fastest and more momentum then your opponents in order to beat through them. With speed and size, these two factors may decide whether you can block a guy or plow through them. Its also conserved from when someone strikes another opponent and then it gets transfered to the other player or ball which then leads to the balls forward velocity. With change in momentum, that also leads to impluse where one can try to absorb the shock with his body and padding against the momentum of a tackle to prevent injury when the momentum is transfered. When you absorb shock, you slow down impuls and reduce chance of injury.
Energy is also a factor where the energy from the players body (chemical) is changed into mechanical energy because its being conserved and then transfered to the ball resulting in the objects motion and action in the game. Energy is the fuel of the players and action of the game.
Force is another element involved with the sport. Forces include gravity, work and friction. The force of gravity contributes to the ball and punting of the game which makes it difficult to kick the ball far and you must compensate with extra strength. Also, force of work where it takes lots of work and energy, time and distance to force the guys in a specific fashion or hold them off while the ball is either ran or thrown. Also friction in the air and ground is what contributes to the players slowing down from their cleats against turf and also the air slowing down the velocity and acceleration of the ball in the air.
Lastly projectile motion involves the ball in the air which can be measured with the time spent in flight, distance traveled and speed of the ball which deal withe the motion of the football in air.
All these components make up the physic fundamentals of the game.