Question on Terminal Velocity finding time

lundi 2 septembre 2013

1. The problem statement, all variables and given/known data

I have two skydivers umping out of a plane at 5000m . Skydiver A is using extended arms and reaching a terminal velocity of 41.53m/s. Skydiver B jumping 20 second later headdown and reaching a terminal velocity at 90 m/s. The question is to find the time the second diver must dive in the headdown position to reach Skydiver A. I know the drag forces for each of the skydivers. Cofnused on how to find the time. The answer of the time is 37 seconds but not sure how to get there

2. Relevant equations

kinematics? vf=vi + at

3. The attempt at a solution

im not sure I tried using vf^2=vi^2+ 2as to find distance from the earth

but the number didnt make sense to me. I think I got 88 m from earth to reach

terminal velocity... not sure...