# Skydiver plans freefall from 25 mi

Discussion in 'General Chat' started by blackwood, Aug 13, 2007.

1. #26
Last edited by a moderator: Apr 25, 2016
he will be breaking the sound barrier ABOVE the ozone layer, when the air starts getting thicker, im sure he will be slowed gradually to his terminal velocity and it wont be a problem

the air pressure at 40k m is only .0014bar, and at the ozone layer, its only .031bar. only at about 1200 meters does the pressure become even remotely normal .2bar, and then it steadily rises to 1 bar at 0meters
it shouldnt be a problem

http://www.legrandsaut.org/

2. #27
it's just a huge pressure wave...so you'd have seriously high pressure all around you...probably really hot too...

3. #28
no...and it's not an explosion either

the pressure wave will just propogate away from him...he'll not hear another sonic boom

4. #29
im pretty sure sound is the hardest metal known to man.

5. #30
Assuming one is formed, he won't hear it at all.

6. #31
Funnily enough I was watching a video of Kittinger's jumps last night. That shit is badass.

7. #32
Second, behind diamonds.

8. #33
Dragonforce is the hardest metal known to man.

9. #34
Last edited by a moderator: Apr 25, 2016
hell be at his terminal velocity after about 20 seconds all the way till he pulls his chute

10. #35

11. #36
The actual speed of sound varies depending on the altitude above sea level because sound travels at slightly different speeds at different temperatures, and the temperature varies according to altitude. At sea level, the speed of sound is about 761 miles per hour (1,225 kilometers per hour). At 20,000 feet (6,096 meters), the speed of sound is 707 miles per hour.

If an aircraft is traveling at one half the speed of sound, it is said to be traveling at Mach 0.5. A speed of Mach 2 is twice the speed of sound. Because the speed of sound varies, a particular speed at sea level expressed as a Mach number would be faster than the same speed at 30,000 feet (9,144 meters), which would be faster than the same speed at 40,000 feet (12,192 meters). In other words, Mach 2 at sea level is a greater number of miles per hour (or kilometers per hour) than Mach 2 at 30,000 feet, which is a greater number of miles per hour than Mach 2 at 40,000 feet. When an aircraft reaches Mach 1, it is said to "break the sound barrier."

Altitude in feet Speed of Sound ratio
Sea Level 1.00
5,000 ft 0.9827
10,000 ft 0.9650

15,000 ft 0.9470
20,000 ft 0.9287
25,000 ft 0.9100

30,000 ft 0.8909
35,000 ft 0.8714
40,000 ft 0.8671

50,000 ft 0.8671
60,000 ft 0.8671

12. #37
do you even know what terminal velocity is you stupid f*ck?

13. #38
Yes

14. #39
Last edited by a moderator: Apr 25, 2016

Make sure you have headphones on.

15. #40
then u know im right

16. #41
c = (C/p)^.5
(Edit: little c = speed of sound, big C = coefficient of stiffness, p = density)

In the atmosphere temperature has a good deal of play over the variables, but temperature is not the end-all reason for differences in the speed of sound.

17. #42
Terminal velocity is the speed at which the force of gravity on a falling object is countered by the force of drag.

mg = 1/2*pv^2AC(drag)

mass, frontal area, and drag coefficient are all constant regardless of changes in altitude, however fluid density (represented by p) and gravity (g) are not.

18. #43
you are not right

19. #44
true i was also wondering about the denisty of the air

20. #45
yes i am, his terminal velocity is governed by the drag, once he freefalls for a bit he hits TV then, this will slowly decrease in speed as teh air gets denser. He is at terminal velocity the whole time pretty much.

21. #46
Burner is right.

In physics, terminal velocity is the velocity at which the drag force of a falling object equals the weight of the object due to gravity.

There is no rule that says terminl velocity cannot vary all the way down to the ground from 130,000 feet.

Initially the skydiver will fall until the drag on him equals his weight at a given height.

22. #47
He'll be at terminal velocity after he pulls his chute too.

23. #48
I was pointing out that Lazy kid knew what terminal velocity was and burner was wrong for correcting it.

24. #49
EliseS2 works for Boeing. You think NASA fakes the color of Mars

Nuff said

25. #50
-1 for not writing it as v=

Oh, and unless he manages to stay in the exact same orientation (which is possible), and unless the air through which he is passing doesn't change velocity (which is highly UNlikely), both CD and A will change.