Terminal velocity is the maximum constant velocity that an object, including a human body, can achieve while falling through a fluid medium such as the Earth's atmosphere. It occurs when the force of gravity pulling the object downward is balanced by the opposing force of air resistance pushing upward.
When a human body reaches terminal velocity during free fall, it means that the gravitational force and the air resistance force are equal in magnitude, resulting in no further acceleration. At this point, the person is falling at a constant velocity, typically around 53 m/s (about 120 mph) for a skydiver in a belly-to-earth orientation.
While tucking and rolling can help to distribute the impact forces more evenly and potentially reduce the chance of specific injuries, it does not eliminate the effects of terminal velocity on the human body. Here are a few reasons why a person would not survive terminal velocity:
Impact forces: Even with a tucked and rolled posture, the impact forces experienced upon hitting the ground or a solid surface at terminal velocity are incredibly high. The body undergoes a sudden deceleration over a very short period, leading to severe trauma and potential internal injuries.
Energy dissipation: The kinetic energy of a person falling at terminal velocity is extremely high due to the large mass and high velocity. It is challenging to dissipate this energy quickly enough to prevent severe injury or death, even with a well-executed roll.
Structural limitations: Human bodies have inherent structural limitations that make them vulnerable to the extreme forces involved at terminal velocity. Bones can fracture, internal organs can be damaged, and the brain can experience severe acceleration-deceleration forces, leading to concussions or other traumatic brain injuries.
Other factors: There are additional factors to consider, such as the height from which the person falls, the type of surface they impact, and the specific body position during the fall. All these factors contribute to the severity of the impact forces and the likelihood of survival.
In summary, terminal velocity represents a state of equilibrium between gravity and air resistance during free fall. While adopting a tucked and rolled position may have some benefits in distributing forces, the high energy and impact forces involved at terminal velocity make it extremely difficult for a human body to survive such an event.