|MadSci Network: Biophysics|
Newton's laws cannot directly describe the kinetics of a parachutist. The system i.e., parachutist + parachute, attains terminal velocity within no time after the parachute is thrown open. Although the initial velocity of two parachutists are same, their terminal velocity can be different depending on their weight, the way they sail by controlling the directions and many other random factors such as wind direction, controls of parachute, etc. With the influence of wind, they can also attain velocity in lateral directions, which is a commonly observed thing. All these random factors can lead to a large difference in velocity between two parachutists, which is sufficient to receive the injury when collided. The collision can be either lateral or more likely, in an angle. However, the relation P=m*v is still applicable at the time of collision if the direction and velocity is known at the time of collision. In the case of Dana Bowman also, the collision was lateral while performing crisscross drive in mid air.
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