A sky diver of mass 80.9 kg (including outfit and equipment) floats down suspended from her parachute, having reached terminal speed. The drag coefficient is 0.575, and the area of her parachute is 20.27 m2. The density of air is 1.14 kg/m3. What is the air's drag force on her? (upward is positive, downward negative)

6 answers

I am only going to do this one. I have already taken this course. It is your turn.
This problem is trivial since there is no acceleration.
The weight m g = the air drag force
= 80.9*9.81 = 794 Newtons

However much more interesting would be the speed which you could get as follows:
Fup = .5 rho v^2 A Cd
Fdown = -m g
sum = m a = 0

.5 (1.14) v^2 (20.27)(.575) = 80.9 (9.81)
why you don't help me for anothers. if ý don't pass this lesson my schollarship is going to cut... please if you can do anotherss for me
Try yourself, post work.
is problem ý don't know any idea for physics... anyy.. because of these ý cant pass thes exam since 2 years... and knýw the teacheser give us the homeworks and ýf ý did this homeworks ý can possiblity to pass 30% pleasee.
I do not like to be mean but it is not my task to just do your home work for you. If you get stuck that is what we are here for. However we do not just plow ahead and do all the problems. It would be great practice for me but I have been doing these since 1954. You are the one who is supposed to be learning and you would not learn much by simply copying my solutions. Try a problem.
ý think is not too much hard for you to do anothers.. if you want to help me ok. if you don't is your opinion:S:S