Free fall equations Sky diver Felix need some help please

[najat]

free fall equations ...Sky diver Felix :) need some help please

hi :)

OK..i tried to use the equations below to evaluate the distance or the time at which felix will reach the speed of sound ...but i failed ..i need some help:
here what i did:

first i neglect the air resistance , but the result was unreasonable so i used these:

i assumed that :

m=weight of felix=70 kg
h=the height=36000 m
k=air resistance=0.24 >> i think "k" during the falling and by the time will be increased to 70

the result was :
t=2.7*10^56 sec :0
v=53 m/s :(

i don't know what i miss here ! so if someone will help me i will be so tankful ..

 

[najat]

hi ..
any body have any idea :(

by the way this is not for home work , it just a question pop up to me and i want to solve it , but it has been moved here :)

 

[CWatters]

Just for info...

http://hypertextbook.com/facts/JianHuang.shtml

"An hour and thirty-one minutes after launch, my pressure altimeter halts at 103,300 feet. At ground control the radar altimeters also have stopped-on readings of 102,800 feet, the figure that we later agree upon as the more reliable. It is 7 o'clock in the morning, and I have reached float altitude …. Though my stabilization chute opens at 96,000 feet, I accelerate for 6,000 feet more before hitting a peak of 614 miles an hour, nine-tenths the speed of sound at my altitude."

Scroll down that page for the maths.