Felix Baumgartner, an Austrian skydiver, jumped from a balloon at an altitude of 38,963.3 meters, and fell into history. He was in free fall for 4 minutes 19 seconds, and on the way down reached the speed of 1,357.64 km/h

What if there had been no air? How long would it have taken him to reach 1357.64 km/hr? How long did it actually take him to reach this speed?

In the absence of air, how long would it have taken him to reach the ground, and what speed would he have reached by the time he got there?

For Felix's fall, is his downward acceleration the same all the way down?

1 answer

a: no resistance,
vf=g*t
change speed to m/s
vf=1357.64km/hr*1hr/3600sec*1000m/1km
vf=377.1 m/s
t= 377.1/9.8=38 seconds with no air resistance
<how long did it actually take to reach the speed?>
avg speed= distance/time=38.96km/259sec=150m/s
so you can figure the average speed during the accelerating time, and a terminal speed for the rest.
ta= time accelerating
tt= time terminal
ta+tt=259sec
150*ta+377(259-ta)=38.96km
solve for ta.

<free fall:
d=1/2 g t^2
t=sqrt 2*38.9k/9.8=sqrt(7930)=89 sec
final speed:
vf=g*t=9.8*89 m/s