The sport of American football often involves athletes running at high speeds and smashing into each other. While they wear protective pads and helmets, their bodies still experience large decelerations and forces. In fact, some of the collisions between players, or between a player and the ground, are comparable to what a person might endure in an automobile accident. In 2017, a large study found that 110 out of 111 deceased NFL players had chronic traumatic encephalopathy (CTE), a degenerative brain disorder associated with repetitive head trauma (see photo). Other studies have linked CTE to higher rates of early onset dementia and memory loss. Consider an NFL player running at 3.92 m/s. During a collision and tackle, his head is brought to a stop in a distance of 0.125 m. (a) Calculate the magnitude of the deceleration of the player's head (assume the deceleration to be constant and treat this as a one-dimensional problem). How does it compare to the acceleration of gravity near the surface of the Earth? (b) Assume the mass of the player's brain is 1.35 kg and calculate the force experienced by the brain.

The sport of American football often involves athletes running at high speeds and smashing into each other. While they wear protective pads and helmets, their bodies still experience large decelerations and forces. In fact, some of the collisions between players, or between a player and the ground, are comparable to what a person might endure in an automobile accident. In 2017, a large study found that 110 out of 111 deceased NFL players had chronic traumatic encephalopathy (CTE), a degenerative brain disorder associated with repetitive head trauma (see photo). Other studies have linked CTE to higher rates of early onset dementia and memory loss. Consider an NFL player running at 3.92 m/s. During a collision and tackle, his head is brought to a stop in a distance of 0.125 m. (a) Calculate the magnitude of the deceleration of the player's head (assume the deceleration to be constant and treat this as a one-dimensional problem). How does it compare to the acceleration of gravity near the surface of the Earth? (b) Assume the mass of the player's brain is 1.35 kg and calculate the force experienced by the brain.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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