if you jumped from a 100 storey building onto a giant inflatable 'safety bed' - would you still get injured ?

if you drop  100 storys   at a  4 meter per story  level 

the calculations are not finished  I used simple example to  tell  but  I got mixed up with the distance as I Did the question;

basically the  speed will be faster and  that means the  speed will be greater and  thus the acceleration will be more when slowing down

that is 400 m

your acceleration will be  9.8 m/s/s 

that means  when you jump off the   building your speed will be 9.8 m/s after one second

and 19.6 after 2 seconds

after 3 seconds speed will be  29.4 m/s

after 3 seconds  the most you could have travelled is  29.4 + 19.6 + 9.8

which is  58.8 m

after 4 seconds the speed will be   39.2 m/s

then  after 5 seconds it will be  49 m/s

when you land safely you have to decelerate  from roughly 49 m/s  to 0 

acceleration like that would hurt   say you can stand   3 g's 

that is   27 + 2.4 = 29.4 m/s/s

that would need  2 SECONDS   to  drop from 49 m/s 

you could not do that with  a   inflatable bed 

if you land wrong.....you might knee yourself in the head.  could happen at one story.

people survive drops like that, but they land going downhill and roll alot to absorb the impact.  still break both legs.

if you had a chain o bouncy castles, and they hit each one, then sure.....minus their legs

It's doubtful you could survive, unless you are a stuntman 

Depends on HOW THICK the bed is and how fast or slow the air is released to gradually decelerate you.  Such "Safety beds" release air upon striking them and gradually slow you down----often used in movies for stunts.   I do not know what the record is.

try it and find out !!!

If carefully designed so the bed would decelerate the person safely then it could be done. 

people have lived from jumping out of airplanes somehow...thought not pretty,,,so yes you would at least be way way better off than those 

depends on the size of this "safety bed". You would be moving at terminal velocity, about 200-300 km/hr depending on angle.

300 km/hr = 83 m/s

if you take 20g as max impact deacceleration, that is about 200 m/s²

v² = v₀² + 2ad

d = 83²/2•200 = 17 meters

in other words, that "safety bed" would have to be 17 m thick. And that assumes the deacceleration is linear, which it is not.

if you take 40g as max impact deacceleration, that is about 400 m/s²

d = 8.7 m

Yes. The force with which you would hit the “safety” bed due to your acceleration and velocity would hurt if not kill you.

Your brother is correct. Jumping from a 100 storied building and then going into the free fall without having anything like a parachute to slow down the sudden deceleration once you hit the safety bed is dangerous. You most likely will be injured.