Why does catching someone or something falling in most cases negate or reduce the injury/damage applied to it? Shouldn’t it be almost just as damaging, just a few feet further up?
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Catching someone (at least form a smaller height) slows down their momentum gradually instead of suddenly. Sudden changes of momentum have a lot of force, and that is the force that harms the human body. However, slower changes in momentum results in lower forces.
It’s similar to the difference between punching someone, and slowly pushing them away with a closed fist. The former hurts, but the latter not so much.
if you try to catch them without absorbing the impact in any way, it wont be much different from them just hitting the ground
the idea is to catch them in a way that will bleed enough energy from the impact to survive.
kind of like crumple zones in a car, they’re designed to crumple and fold and take a lot of energy from an impact to keep it from being transmitted to the occupants.
except in this scenario, the catcher is acting as a living crumple zone, using their body to disperse the energy from an impact
Because when you catch something, your hands aren’t immovable concrete-hard slabs of meat made metal. Your flesh is soft and squishy and your arms have give. Concrete will extert all that force slowing you down with the space of millimeters, if that. When you catch something, you can slow it down over the span of a few feet. It decreases the maximum acceleartion the thing has to survive through.
Concrete: A whole lot of acceleration all at once. You stop really fast.
Caught in the swashbuckling arms of the hero: A smaller amount of acceleration over a span of time. You stop, but slower. There are limits though, even if he doesn’t drop you.
It’s how cushions and foam works. You start decelerating as soon as you hit the foam, and the foam squishes applying more and more resistance. You could hit something at relativistic speeds and with enough padding have a comfortable 1g of acceleration as you came to a stop.
Force = mass x acceleration. The faster something decelerates the more force is applied.. when you catch something the correct way, you are gradually reducing its speed and apply less force
Firstly, catching someone means they won’t hit a potentially hard surface like concrete which can break bones and tear flesh.
Secondly, catching someone you’re able to use your muscles to apply an upward force to decelerate them from falling, over several inches or even a foot or more. So the momentum instead of going to 0mph in an instant, does so over time. You catching the person displaces the kinetic energy over your own body.
Of course, this only works so well. Depending on the height of which you catch the person from and their weight, it’s possible that they are still severely injured or die, or cause injury to the catching individual. If a 18 year old girl jumps. Out of a 10 story apartment building and someone tries. To catch her, it won’t end so well.
let’s change perspective, imagine throwing a ball against a trampoline, the trampoline stretches on impact with the ball, absorbing the motion energy of the ball and distributing the force. on the other hand, in the case of grabbing a falling person, the body of the person who grabs it absorbs part of the force of the falling body, distributing the force of impact.
landing on something like the floor decerates very abrubtly. whereas catching it decerates it slowly.
think of dropping an egg, then tossing an egg in the air and catching it. the chances of the egg smashing when you catch it is small if you manage to catch it. but if you drop it on the floor, the chance of it cracking is quite large because the deceleration is much more abrupt.
Simple test. Jump in the air and land normally with your legs and hips bending to absorb the impact. Now jump and keep a completely rigid leg and hip stature and you will feel a huge difference in impact. The person catching you is doing the same thing your legs do when you land from a jump.
What you see in the movies is wrong.
When Superman catches that person who fell out of a plane a second before impact, that person is now dead.
As many others have pointed out, catching increases the time during which deceleration occurs thus reducing maximum experienced g-force (thanks air bags). This will work to a point. Try catching a 200 lb man jumping from a 4 story building–you’ll probably both be crushed.
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