I would like to know how some people survived plane crash even after falling from thousands of feet high above the ground? I read that a person cannot survive after falling over 85 feet high but how those people survived?
Answer First, those survivals are extraordinarily rare. Second, 85 feet is a guideline and not some hard human limit. There are an enormous number of factors which affect the condition of a human body after any impact, and considerable variation in how individual bodies will react to a fall. trained movie stunt doubles falling on airbags fall these heights without injury all the time, due to their training and the nature of what they're landing on. An elderly person falling from a building onto concrete is highly unlikely to survive a similar fall, however. People known to have survived falls were often skydivers wearing clothing designed to slow their fall, who happened to fall into swamps an on other soft surfaces. The human body reaches a maximum speed (different for each person) called terminal velocity, where the force of drag upwards equals the force of gravity downward (their weight). At that point, the person stops accelerating towards the ground. Their survival of impact from then depends on how high their terminal velocity is, what they land on (how fast they slow to a stop), what parts of their body might land first to help slow them before vital organs hit the ground, and the strength of the person falling. It's still extremely rare, many things have to go right for anyone falling from such heights to actually survive.
I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.
I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.
Education/Credentials Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.