The Physics of Dodgeball

              Most students who went to elementary school have played dodgeball in gym class. I mentor at an elementary school, and the kids always ask us to play. After we start and the soft, foam balls fly across the gym, there is an increasing potential for injury. While the balls are less likely to hurt me, the smaller students had a higher likelihood of being injured, primarily because of physics.

              Being bigger and having more strength, the other mentors and I had to be cautious of how hard we threw the ball. We can produce a larger velocity using less force than some of the students. This would increase the kinetic energy of the ball given KE=1/2mv². The harder a ball was thrown, the greater the force, and therefore, the greater the velocity. When these balls came into contact with the opponent more energy would be absorbed in the point of contact. Newton’s First Law states that an object in motion stays in motion unless acted upon by an outside force. In this case, the reactionary force is the body's response to getting hit by a ball.

              Another risk for injury arises depending on the body parts that were hit. Areas like the face have less distance over which the ball will decelerate, resulting in a larger acceleration rate and greater absorption of force given F=ma. If someone got hit in the leg, for example, there would be a greater distance over which deceleration occurred because there is more muscle, which will produce a smaller acceleration and smaller absorbed force.

              Given an understanding of physics concepts, a game of dodgeball can be made safer. By ensuring lighter balls are being used (like balls made of foam), the kinetic energy will be reduced by reducing the mass variable. More so, by having a rule of no headshots or aiming below the waist, it ensures that contact is being made in locations with a greater distance of deceleration, reducing the risk of injury. Finally, making sure that taller individuals are conscious that they can throw the ball with a greater force helps reduce the risk of injury. Gentle throws or underhand tosses can reduce the velocity of the ball which helps further prevent injury. These tactics help make dodgeball a fun gym activity that will not hurt its participants.

https://www.fatherly.com/health-science/getting-hit-by-a-baseball-injuries-physics/ (A more extreme version than getting hit with a dodgeball)