Football Collision

     As a football player, I wanted to understand the physics of a collision between two football players. Everyday, a football player takes part in countless collisions with their teammates and prospective opponents, but the question is how hard is this collision? How much force is one player exerting on another?

    We're going to look at one play that occurred in the Clemson vs Syracuse game in 2017: 

    A Syracuse Defensive player reads the play and comes to make a tackle on the opposing team's wide receiver. We see the defensive player get low in his stance to make a textbook tackle on the offensive player resulting in a huge hit. The reason as to why the defensive player got lower in his stance is to attack the center of gravity of the opponent. By doing this, he has a better probability of getting the opposing player on the ground, but also achieves a greater impact during the collision. Here we will analyze the collision between these two players and how much momentum the defensive player is generating. 

(the video on here isn't working so if you're curious what the hit looked like click the link below and forward to 6:34)

https://youtu.be/cQfv6rpqx4A 

To understand this collision, we use two formulas: 

By using tracker, we find the velocity that which the football player accelerates to hit the stationary player. 

• Initial velocity of moving player: 6.05 m.s 
• Initial velocity of still player: -1.33 m/s 
• Final velocity of both players: 3.03 m/s 

    By using these values, we can calculate the momentum for both individuals and see the final momentum after the collision. We know that the momentum before the collision is equal to the momentum after the collision, so we can use the equation below, which  deals with conservation of momentum, to understand how much force was used in the tackle. 

    We find the initial momentum, prior to the collision to be 469.5 kg*m/s and the final momentum to be 579.1 kg*m/s. We understand that the difference in momentum is due to outside forces such as the normal force exerting a force from the ground. Through this equation we find that in 0.2 seconds, a net force of 548 Newtons occur after the collision of both players. But if we just analyze the player accelerating, we see that he pushes off the ground with a net force of 2577 Newtons. As we can see, football players generate a great amount of force when expecting a collision, and in turn, the hits can be very painful and devastating. 

Works Cited: 

https://www.wired.com/story/how-to-deconstruct-a-football-tackle-with-physics/